- ichthyicadj.Fish-like
- ichthyologyn.The branch of zoology that treats of fishes
- ichthyosaursn.A fossil reptile
- icilyadv.Frigidly
- icinessn.The state of being icy
- iconn.An image or likeness
- iconoclastn.An image-breaker
- idealizev.To make to conform to some mental or imaginary standard
- idiomn.A use of words peculiar to a particular language
- idiosyncrasyn.A mental quality or habit peculiar to an individual
- idolizev.To regard with inordinate love or admiration
- ignobleadj.Low in character or purpose
- ignominiousadj.Shameful
- Iliadn.A Greek epic poem describing scenes from the siege of Troy
- illegaladj.Not according to law
- illegibleadj.Undecipherable
- illegitimateadj.Unlawfully begotten
- illiberaladj.Stingy
- illicitadj.Unlawful
- illimitableadj.Boundless
- illiterateadj.Having little or no book-learning
- ill-naturedadj.Surly
- illogicaladj.Contrary to the rules of sound thought
- illuminantn.That which may be used to produce light
- illuminatev.To supply with light
- illuminev.To make bright or clear
- illusionn.An unreal image presented to the senses
- illusiveadj.Deceptive
- illusoryadj.Deceiving or tending to deceive, as by false appearance
- imaginableadj.That can be imagined or conceived in the mind
- imaginaryadj.Fancied
- imbibev.To drink or take in
- imbroglion.A misunderstanding attended by ill feeling, perplexity, or strife
- imbruev.To wet or moisten
- imitationn.That which is made as a likeness or copy
- imitatorn.One who makes in imitation
- immaculateadj.Without spot or blemish
- immaterialadj.Of no essential consequence
- immatureadj.Not full-grown
- immeasurableadj.Indefinitely extensive
- immenseadj.Very great in degree, extent, size, or quantity
- immersev.To plunge or dip entirely under water or other fluid
- immersionn.The act of plunging or dipping entirely under water or another fluid
- immigrantn.A foreigner who enters a country to settle there
- immigratev.To come into a country or region from a former habitat
- imminencen.Impending evil or danger
- imminentadj.Dangerous and close at hand
- immiscibleadj.Separating, as oil and water
- immoraladj.Habitually engaged in licentious or lewd practices
- immortalizev.To cause to last or to be known or remembered throughout a great or indefinite length of time
- immovableadj.Steadfast
- immuneadj.Exempt, as from disease
- immutableadj.Unchangeable
- impairv.To cause to become less or worse
- impalpableadj.Imperceptible to the touch
- impartialadj.Unbiased
- impassableadj.That can not be passed through or over
- impassibleadj.Not moved or affected by feeling
- impassiveadj.Unmoved by or not exhibiting feeling
- impatiencen.Unwillingness to brook delays or wait the natural course of things
- impeccableadj.Blameless
- impecuniousadj.Having no money
- impedev.To be an obstacle or to place obstacles in the way of
- impelv.To drive or urge forward
- impendv.To be imminent
- imperativeadj.Obligatory
- imperceptibleadj.Indiscernible
- imperfectibleadj.That can not be perfected
- imperilv.To endanger
- imperiousadj.Insisting on obedience
- impermissibleadj.Not permissible
- impersonaladj.Not relating to a particular person or thing
- impersonatev.To appear or act in the character of
- impersuadableadj.Unyielding
- impertinencen.Rudeness
- imperturbableadj.Calm
- imperviousadj.Impenetrable
- impetuosityn.Rashness
- impetuousadj.Impulsive
- impetusn.Any impulse or incentive
- impietyn.Irreverence toward God
- impiousadj.Characterized by irreverence or irreligion
- implausibleadj.Not plausible
- impliableadj.Capable of being inferred
- implicatev.To show or prove to be involved in or concerned
- implicitadj.Implied
- implyv.To signify
- impoliticadj.Inexpedient
- importationn.The act or practice of bringing from one country into another
- importunateadj.Urgent in character, request, or demand
- importunev.To harass with persistent demands or entreaties
- impotentadj.Destitute of or lacking in power, physical, moral, or intellectual
- impoverishv.To make indigent or poor
- impracticableadj.Not feasible
- impregnableadj.That can not be taken by assault
- impregnatev.To make pregnant
- impromptun.Anything done or said on the impulse of the moment
- improperadj.Not appropriate, suitable, or becoming
- improprietyn.The state or quality of being unfit, unseemly, or inappropriate
- improvidentadj.Lacking foresight or thrift
- improvisev.To do anything extemporaneously or offhand
- imprudentadj.Heedless
- impudencen.Insolent disrespect
- impugnv.To assail with arguments, insinuations, or accusations
- impulsionn.Impetus
- impulsiveadj.Unpremeditated
- impunityn.Freedom from punishment
- impureadj.Tainted
- imputev.To attribute
- inaccessibleadj.Difficult of approach
- inaccurateadj.Not exactly according to the facts
- inactiveadj.Inert
- inadequateadj.Insufficient
- inadmissibleadj.Not to be approved, considered, or allowed, as testimony
- inadvertentadj.Accidental
- inadvisableadj.Unadvisable
- inaneadj.Silly
- inanimateadj.Destitute of animal life
- inapprehensibleadj.Not to be understood
- inaptadj.Awkward or slow
- inarticulateadj.Speechless
- inaudibleadj.That can not be heard
- inbornadj.Implanted by nature
- inbredadj.Innate
- incandescencen.The state of being white or glowing with heat
- incandescentadj.White or glowing with heat
- incapacitatev.To deprive of power, capacity, competency, or qualification
- incapacityn.Want of power to apprehend, understand, and manage
- incarceratev.To imprison
- incendiaryn.Chemical or person who starts a fire-literally or figuratively
- incentiven.That which moves the mind or inflames the passions
- inceptionn.The beginning
- inceptiveadj.Beginning
- incessantadj.Unceasing
- inchmealadv.Piecemeal
- inchoateadj.Incipient
- inchoativen.That which begins, or expresses beginning
- incidencen.Casual occurrence
- incidentn.A happening in general, especially one of little importance
- incidentallyadv.Without intention
- incineratev.To reduce to ashes
- incipiencen.Beginning
- incipientadj.Initial
- incisorn.A front or cutting tooth
- incitev.To rouse to a particular action
- incitementn.That which moves to action, or serves as an incentive or stimulus
- incoercibleadj.Incapable of being forced, constrained, or compelled
- incoherencen.Want of connection, or agreement, as of parts or ideas in thought, speech, etc
- incoherentadj.Not logically coordinated, as to parts, elements, or details
- incombustibleadj.That can not be burned
- incomparableadj.Matchless
- incompatibleadj.Discordant
- incompetencen.General lack of capacity or fitness
- incompetentadj.Not having the abilities desired or necessary for any purpose
- incompleteadj.Lacking some element, part, or adjunct necessary or required
- incomprehensibleadj.Not understandable
- incompressibleadj.Resisting all attempts to reduce volume by pressure
- inconceivableadj.Incomprehensible
- incongruousadj.Unsuitable for the time, place, or occasion
- inconsequentialadj.Valueless
- inconsiderableadj.Small in quantity or importance
- inconsistentadj.Contradictory
- inconstantadj.Changeable
- incontrovertibleadj.Indisputable
- inconvenientadj.Interfering with comfort or progress
- indefensibleadj.Untenable
- indefinitelyadv.In a vague or uncertain way
- indelibleadj.That can not be blotted out, effaced, destroyed, or removed
- indescribableadj.That can not be described
- indestructibleadj.That can not be destroyed
- indicantadj.That which points out
- indicatorn.One who or that which points out
- indictv.To find and declare chargeable with crime
- indigencen.Poverty
- indigenousadj.Native
- indigentadj.Poor
- indigestibleadj.Not digestible, or difficult to digest
- indigestionn.Difficulty or failure in the alimentary canal in changing food into absorptive nutriment
- indignantadj.Having such anger and scorn as is aroused by meanness or wickedness
- indignityn.Unmerited contemptuous conduct or treatment
- indiscernibleadj.Not perceptible
- indiscreetadj.Lacking wise judgment
- indiscriminateadj.Promiscuous
- indispensableadj.Necessary or requisite for the purpose
- indistinctadj.Vague
- indivertibleadj.That can not be turned aside
- indivisibleadj.Not separable into parts
- indolencen.Laziness
- indolentadj.Habitually inactive or idle
- indomitableadj.Unconquerable
- inductv.To bring in
- indulgencen.The yielding to inclination, passion, desire, or propensity in oneself or another
- indulgentadj.Yielding to the desires or humor of oneself or those under one's care
- inebriatev.To intoxicate
- inedibleadj.Not good for food
- ineffableadj.Unutterable
- inefficientadj.Not accomplishing an intended purpose
- inefficiencyn.That which does not accomplish an intended purpose
- ineligibleadj.Not suitable to be selected or chosen
- ineptadj.Not fit or suitable
- inertadj.Inanimate
- inestimableadj.Above price
- inevitableadj.Unavoidable
- inexcusableadj.Not to be justified
- inexhaustibleadj.So large or furnishing so great a supply as not to be emptied, wasted, or spent
- inexorableadj.Unrelenting
- inexpedientadj.Unadvisable
- inexpensiveadj.Low-priced
- inexperiencen.Lack of or deficiency in experience
- inexplicableadj.Such as can not be made plain
- inexpressibleadj.Unutterable
- inextensibleadj.Of unchangeable length or area
- infallibleadj.Exempt from error of judgment, as in opinion or statement
- infamousadj.Publicly branded or notorious, as for vice, or crime
- infamyn.Total loss or destitution of honor or reputation
- inferencen.The derivation of a judgment from any given material of knowledge on the ground of law
- infernaladj.Akin to or befitting hell or its occupants
- infestv.To be present in such numbers as to be a source of annoyance, trouble, or danger
- infideln.One who denies the existence of God
- infidelityn.Disloyalty
- infiniteadj.Measureless
- infinityn.Boundless or immeasurable extension or duration
- infirmadj.Lacking in bodily or mental strength
- infirmaryn.A place for the reception or treatment of the sick
- infirmityn.A physical, mental, or moral weakness or flaw
- inflammableadj.Easily set on fire or excited
- inflammationn.A morbid process in some part of the body characterized by heat, swelling, and pain
- inflexibleadj.That can not be altered or varied
- influencen.Ability to sway the will of another
- influentialadj.Having the power to sway the will of another
- influxn.Infusion
- infrequencen.Rareness
- infrequentadj.Uncommon
- infringev.To trespass upon
- infusev.To instill, introduce, or inculcate, as principles or qualities
- infusionn.The act of imbuing, or pouring in
- ingeniousadj.Evincing skill, originality, or cleverness, as in contrivance or arrangement
- ingenuityn.Cleverness in contriving, combining, or originating
- ingenuousadj.Candid, frank, or open in character or quality
- ingloriousadj.Shameful
- ingraftv.To set or implant deeply and firmly
- ingratiatev.To win confidence or good graces for oneself
- ingratituden.Insensibility to kindness
- ingredientn.Component
- inherencen.The state of being permanently existing in something
- inherentadj.Intrinsic
- inhibitv.To hold back or in
- inhospitableadj.Not disposed to entertain strangers gratuitously
- inhumanadj.Savage
- inhumev.To place in the earth, as a dead body
- inimicaladj.Adverse
- iniquityn.Gross wrong or injustice
- initiatev.To perform the first act or rite
- injectv.To introduce, as a fluid, by injection
- injunctionn.Mandate
- inklingn.A hint
- inlandadj.Remote from the sea
- inletn.A small body of water leading into a larger
- inmostadj.Deepest within
- innocuousadj.Harmless
- innovatev.To introduce or strive to introduce new things
- innuendon.Insinuation
- innumerableadj.Countless
- inoffensiveadj.Causing nothing displeasing or disturbing
- inopportuneadj.Unsuitable or inconvenient, especially as to time
- inquirev.To ask information about
- inquisitionn.A court or tribunal for examination and punishment of heretics
- inquisitiveadj.Given to questioning, especially out of curiosity
- inquisitorn.One who makes an investigation
- inroadn.Forcible encroachment or trespass
- insatiableadj.That desires or craves immoderately or unappeasably
- inscribev.To enter in a book, or on a list, roll, or document, by writing
- inscrutableadj.Impenetrably mysterious or profound
- insecureadj.Not assured of safety
- insensibleadj.Imperceptible
- insentientadj.Lacking the power of feeling or perceiving
- inseparableadj.That can not be separated
- insidiousadj.Working ill by slow and stealthy means
- insightn.Intellectual discernment
- insignificancen.Lack of import or of importance
- insignificantadj.Without importance, force, or influence
- insinuatev.To imply
- insipidadj.Tasteless
- insistencen.Urgency
- insistentadj.Urgent
- insolencen.Pride or haughtiness exhibited in contemptuous and overbearing treatment of others
- insolentadj.Impudent
- insomnian.Sleeplessness
- inspectorn.An official appointed to examine or oversee any matter of public interest or importance
- instancen.A single occurrence or happening of a given kind
- instantn.A very brief portion of time
- instantaneousadj.Done without perceptible lapse of time
- instigatev.To provoke
- instigatorn.One who incites to evil
- instillv.To infuse
- instructiveadj.Conveying knowledge
- insufficiencyn.Inadequacy
- insufficientadj.Inadequate for some need, purpose, or use
- insularadj.Pertaining to an island
- insulatev.To place in a detached state or situation
- insuperableadj.Invincible
- insuppressibleadj.Incapable of being concealed
- insurgencen.Uprising
- insurgentn.One who takes part in forcible opposition to the constituted authorities of a place
- insurrectionn.The state of being in active resistance to authority
- intangibleadj.Not perceptible to the touch
- integrityn.Uprightness of character and soundness of moral principle
- intellectn.The faculty of perception or thought
- intellectualadj.Characterized by intelligence
- intelligencen.Capacity to know or understand
- intelligibleadj.Comprehensible
- intemperancen.Immoderate action or indulgence, as of the appetites
- intensionn.The act of stringing or stretching, or state of being strained
- intensiveadj.Adding emphasis or force
- intentionn.That upon which the mind is set
- interactv.To act reciprocally
- intercedev.To mediate between persons
- interceptv.To interrupt the course of
- intercessionn.Entreaty in behalf of others
- intercessorn.A mediator
- interdictn.Authoritative act of prohibition
- interimn.Time between acts or periods
- interlocutorn.One who takes part in a conversation or oral discussion
- interluden.An action or event considered as coming between others of greater length
- intermediateadj.Being in a middle place or degree or between extremes
- interminableadj.Having no limit or end
- intermissionn.A recess
- intermitv.To cause to cease temporarily
- intermittentadj.A temporary discontinuance
- interpolationn.Verbal interference
- interposev.To come between other things or persons
- interpositionn.A coming between
- interpretern.A person who makes intelligible the speech of a foreigner by oral translation
- interrogatev.To examine formally by questioning
- interrogativeadj.Having the nature or form of a question
- interrogatoryn.A question or inquiry
- interruptv.To stop while in progress
- intersectv.To cut through or into so as to divide
- intervalen.A low tract of land between hills, especially along a river
- intervenev.To interfere for some end
- intestacyn.The condition resulting from one's dying not having made a valid will
- intestateadj.Not having made a valid will
- intestinen.That part of the digestive tube below or behind the stomach, extending to the anus
- intimacyn.Close or confidential friendship
- intimidatev.To cause to become frightened
- intolerableadj.Insufferable
- intolerancen.Inability or unwillingness to bear or endure
- intolerantadj.Bigoted
- intoxicantn.Anything that unduly exhilarates or excites
- intoxicatev.To make drunk
- intracellularadj.Occurring or situated within a cell
- intramuraladj.Situated within the walls of a city
- intrepidadj.Fearless and bold
- intricacyn.Perplexity
- intricateadj.Difficult to follow or understand
- intriguen.A plot or scheme, usually complicated and intended to accomplish something by secret ways
- intrinsicadj.Inherent
- introductoryadj.Preliminary
- introgressionn.Entrance
- intromitv.To insert
- introspectv.To look into
- introspectionn.The act of observing and analyzing one's own thoughts and feelings
- introversionn.The act of turning or directing inward, physically or mentally
- introvertv.To turn within
- intrudev.To come in without leave or license
- intrusionn.The act of entering without warrant or invitation; encroachment
- intuitionn.Instinctive knowledge or feeling
- inundatev.To fill with an overflowing abundance
- inundationn.Flood
- inurev.To harden or toughen by use, exercise, or exposure
- invalidadj.Having no force, weight, or cogency
- invalidn.One who is disabled by illness or injury
- invalidatev.To render of no force or effect
- invaluableadj.Exceedingly precious
- invariableadj.Unchangeable
- invasionn.Encroachment, as by an act of intrusion or trespass
- invectiven.An utterance intended to cast censure, or reproach
- inveighv.To utter vehement censure or invective
- inventiveadj.Quick at contrivance
- inverseadj.Contrary in tendency or direction
- inversionn.Change of order so that the first shall become last and the last first
- invertv.To turn inside out, upside down, or in opposite direction
- investigatorn.One who investigates
- investorn.One who invests money
- inveterateadj.Habitual
- invidiousadj.Showing or feeling envy
- invigoratev.To animate
- invincibleadj.Not to be conquered, subdued, or overcome
- inviolableadj.Incapable of being injured or disturbed
- invokev.To call on for assistance or protection
- involuntaryadj.Unwilling
- involutionn.Complication
- involvev.To draw into entanglement, literally or figuratively
- invulnerableadj.That can not be wounded or hurt
- inwardlyadv.With no outward manifestation
- iotan.A small or insignificant mark or part
- irascibleadj.Prone to anger
- irateadj.Moved to anger
- iren.Wrath
- iridescencen.A many-colored appearance
- iridescentadj.Exhibiting changing rainbow-colors due to the interference of the light
- irkv.To afflict with pain, vexation, or fatigue
- irksomeadj.Wearisome
- ironyn.Censure or ridicule under cover of praise or compliment
- irradiancen.Luster
- irradiatev.To render clear and intelligible
- irrationaladj.Not possessed of reasoning powers or understanding
- irreducibleadj.That can not be lessened
- irrefragableadj.That can not be refuted or disproved
- irrefrangibleadj.That can not be broken or violated
- irrelevantadj.Inapplicable
- irreligiousadj.Indifferent or opposed to religion
- irreparableadj.That can not be rectified or made amends for
- irrepressibleadj.That can not be restrained or kept down
- irresistibleadj.That can not be successfully withstood or opposed
- irresponsibleadj.Careless of or unable to meet responsibilities
- irreverencen.The quality showing or expressing a deficiency of veneration, especially for sacred things
- irreverentadj.Showing or expressing a deficiency of veneration, especially for sacred things
- irreverentialadj.Showing or expressing a deficiency of veneration, especially for sacred things
- irreversibleadj.Irrevocable
- irrigantadj.Serving to water lands by artificial means
- irrigatev.To water, as land, by ditches or other artificial means
- irritableadj.Showing impatience or ill temper on little provocation
- irritancyn.The quality of producing vexation
- irritantn.A mechanical, chemical, or pathological agent of inflammation, pain, or tension
- irritatev.To excite ill temper or impatience in
- irruptionn.Sudden invasion
- islen.An island
- isletn.A little island
- isobarn.A line joining points at which the barometric pressure is the same at a specified moment
- isochronousadj.Relating to or denoting equal intervals of time
- isolatev.To separate from others of its kind
- isothermaladj.Having or marking equality of temperature
- itinerantadj.Wandering
- itineraryn.A detailed account or diary of a journey
- itineratev.To wander from place to place