impose (v.) Look up impose at
late 14c., "to lay (a crime, etc.) to the account of," from Old French imposer "put, place; impute, charge, accuse" (c. 1300), from assimilated form of in- "into, in" (see in- (2)) + poser "put, place" (see pose (v.1)). Sense of "to lay on as a burden" first recorded 1580s. Related: Imposed; imposing.
imposing (adj.) Look up imposing at
"that impresses by appearance or manner," 1786, from present participle of impose (v.). Related: Imposingly.
imposition (n.) Look up imposition at
late 14c., "the levying of taxes, a tax, duty, tribute," from Old French imposicion "tax, duty; a fixing" (early 14c.), from Latin impositionem (nominative impositio) "a laying on," from imponere "to place upon," from assimilated form of in- "into, in" (see in- (2)) + ponere "to put, place" (past participle positus; see position (n.)). Sense of "the act of putting (something) on (something else)" is from 1590s. Meaning "an act or instance of imposing" (on someone) first recorded 1630s (see impose).
impossibility (n.) Look up impossibility at
late 14c., "quality of being impossible," from impossible + -ity; perhaps from or modeled on French impossibilité. Meaning "an impossible thing or occurrence" is from c. 1500.
impossible (adj.) Look up impossible at
late 14c., from Old French impossible, from Latin impossibilis "not possible," from assimilated form of in- "not, opposite of" (see in- (1)) + possibilis (see possible). Related: Impossibly.
impost (n.) Look up impost at
"tax, duty," 1560s, from Middle French impost, from Medieval Latin impostum, from neuter of Latin impostus, contracted from impositus, past participle of imponere (see impostor).
impostor (n.) Look up impostor at
1580s, from Middle French imposteur (16c.), from Late Latin impostor, agent noun from impostus, collateral form of impositus, past participle of imponere "place upon, impose upon, deceive," from assimilated form of in- "into, in, on, upon" (see in- (2)) + ponere "to put place" (past participle positus; see position (n.)).
imposture (n.) Look up imposture at
"act of willfully deceiving others," 1530s, from Middle French imposture, from Late Latin impostura, from impostus (see impost).
impotence (n.) Look up impotence at
early 15c., "physical weakness," also "poverty," from Middle French impotence "weakness," from Latin impotentia "lack of control or power," from impotentem (nominative impotens); see impotent. In reference to a want of (male) sexual potency, from c. 1500. The figurative senses of the word in Latin were "violence, fury, unbridled passion." Related: Impotency.
impotent (adj.) Look up impotent at
late 14c., "physically weak, enfeebled, crippled," from Old French impotent "powerless, weak, incapable," from Latin imponentem (nominative impotens) "lacking control, powerless," from assimilated form of in- "not, opposite of" (see in- (1)) + ponentem (nominative potens) "potent" (see potent).

Meaning "having no power to accomplish anything" is from mid-15c.; that of "completely lacking in sexual power" (of males) is from mid-15c. Middle English also had a native term for this: Cunt-beaten (mid-15c.). The figurative sense in Latin was "without self-control, headstrong, violent." Related: Impotently.
impound (v.) Look up impound at
early 15c., "to shut up in a pen or pound," from assimilated form of in- "into, in" (see in- (2)) + pound (n.). Originally of cattle seized by law. Related: Impounded; impounding.
impoundment (n.) Look up impoundment at
1660s; see impound + -ment.
impoverish (v.) Look up impoverish at
early 15c., empoverischen, from Old French empoveriss-, stem of empoverir, from em- + povre "poor" (see poor). Related: Impoverished; impoverishing.
impoverishment (n.) Look up impoverishment at
1550s; see impoverish + -ment.
impracticable (adj.) Look up impracticable at
"incapable of being done," 1670s, from assimilated form of in- (1) "not, opposite of" + practicable. Earlier in a sense of "impassable" (1650s).
impractical (adj.) Look up impractical at
1823, from assimilated form of in- (1) "not, opposite of" + practical. Impracticable in the same sense dates from 1670s.
imprecate (v.) Look up imprecate at
1610s, probably a back-formation from imprecation. Related: Imprecated; imprecating; imprecatory (1580s).
imprecation (n.) Look up imprecation at
mid-15c., "a curse, cursing," from Latin imprecationem (nominative imprecatio), from past participle stem of imprecari "invoke, pray, call down upon," from assimilated form of in- "into, in, within" (see in- (2)) + precari "to pray, ask, beg, request" (see pray). "Current limited sense is characteristic of human nature." [Weekley]
imprecise (adj.) Look up imprecise at
1805, from assimilated form of in- (1) "not, opposite of" + precise. Related: Imprecisely.
imprecision (n.) Look up imprecision at
1803, from assimilated form of in- (1) "not, opposite of" + precision.
impregnable (adj.) Look up impregnable at
early 15c., imprenable "impossible to capture," from Middle French imprenable "invulnerable," from assimilated form of in- "not, opposite of" (see in- (1)) + Old French prenable "assailable, vulnerable" (see pregnable). With intrusive -g- 16c., on model of deign, reign, etc. Related: Impregnability.
impregnate (v.) Look up impregnate at
c. 1600, from Late Latin impraegnatus "pregnant," past participle of impraegnare "to render pregnant," from assimilated form of in- "into, in" (see in- (2)) + praegnare "make pregnant" (see pregnant). Earlier in same sense was impregn (1530s).
impregnation (n.) Look up impregnation at
late 14c., "making or becoming pregnant," from Old French impregnacion, from Late Latin impregnationem (nominative impregnatio), from impraegnare (see impregnate).
impresario (n.) Look up impresario at
1746, from Italian impresario "operatic manager," literally "undertaker (of a business)," from impresa "undertaking," fem. of impreso, past participle of imprendere "undertake," from Vulgar Latin imprendere, from assimilated form of in- "into, in, on, onto" (see in- (2)) + prehendere "to grasp" (see prehensile).
imprescriptible (adj.) Look up imprescriptible at
"inalienable, not subject to prescription," 1560s, French imprescriptible (16c.) or a native formation from assimilated form of in- (1) "not, opposite of" + Latin praescriptus, past participle of praescribere "to write beforehand" (see prescribe). Usually with right. Alternative imprescribable is attested from 1887.
impress (v.) Look up impress at
late 14c., "have a strong effect on the mind or heart," from Latin impressus, past participle of imprimere "press into or upon, stamp," from assimilated form of in- "into, in, on, upon" (see in- (2)) + premere "to press" (see press (v.1)). Literal sense of "to apply with pressure, make a permanent image in, indent, imprint" is from early 15c. in English. Sense of "to levy for military service" is from 1590s, a meaning more from press (v.2). Related: Impressed; impressing.
impress (n.) Look up impress at
"act of impressing," also "characteristic mark," 1590s, from impress (v.).
impressed (adj.) Look up impressed at
early 15c., "pressed or forced upon" (the mind), past participle adjective from impress (v.).
impression (n.) Look up impression at
late 14c., "mark produced by pressure," also "image produced in the mind or emotions," from Old French impression "print, stamp; a pressing on the mind," from Latin impressionem (nominative impressio) "onset, attack," figuratively "perception," literally "a pressing into," from imprimere (see impress). Meaning "act or process of indenting" is early 15c.; that of "printing of a number of copies" is from 1570s. Meaning "belief, vague notion" (as in under the impression) is from 1610s.
impressionable (adj.) Look up impressionable at
1836, formed on French model, from impression + -able. Earlier was impressible (1620s).
impressionism (n.) Look up impressionism at
1839 as a term in philosophy, from impression + -ism. Specifically with reference to the French art movement from 1882, from impressionist.
impressionist Look up impressionist at
as a style of painting aiming to represent overall impressions rather than exact details, first attested in English 1876 (adjective and noun), coined in French 1874 by French critic Louis Leroy ("école impressionniste") in a disparaging reference to Monet's sunset painting "Impression, Soleil Levant." Later extended to other arts.
impressionistic (adj.) Look up impressionistic at
1886; see impressionist + -ic.
impressive (adj.) Look up impressive at
1570s, "capable of being easily impressed," from impress + -ive. Meaning "capable of making an impression on the mind or senses" is from 1775. Related: Impressively; impressiveness.
impressment (n.) Look up impressment at
1796, "act of impressing into service," from impress (v.) + -ment.
imprimatur (n.) Look up imprimatur at
1640, Modern Latin, literally "let it be printed," the formula of a book licenser, third person singular present subjunctive passive of Latin imprimere "to print" (see impress). Originally of state license to print books, later only of Roman Catholic Church.
imprint (v.) Look up imprint at
late 14c., from Old French empreinter, from empreinte, noun use of fem. past participle of eimpreindre "to impress, imprint," from Vulgar Latin *impremere, from Latin imprimere "to impress, imprint" (see impress). As a noun from mid-15c.
imprison (v.) Look up imprison at
c. 1300, from Old French emprisoner (12c.), from em- "in" (see in- (2)) + prison (see prison). Related: Imprisoned; imprisoning.
imprisonment (n.) Look up imprisonment at
late 14c., from Anglo-French emprisonement, Old French emprisonement (13c.), from emprisoner (see imprison).
improbability (n.) Look up improbability at
1590s, "fact or quality of being improbably;" see improbable + -ity. Meaning "an instance of something improbable" is from 1610s.
improbable (adj.) Look up improbable at
1590s, from assimilated form of in- (1) "not, opposite of" + probable, or else from Latin improbabilis. Related: Improbably.
imprompt (adj.) Look up imprompt at
(obsolete) 1759, from Latin impromptus "unready, hesitating," from assimilated form of in- "not, opposite of" (see in- (1)) + promptus "ready" (see prompt).
impromptu Look up impromptu at
1660s (adv.), 1764 (adj.), from French impromptu (1650s), from Latin in promptu "in readiness," from assimilated form of in- "into, in, on, upon" (see in- (2)) + promptu, ablative of promptus "readiness," from past participle of promere "to bring out," from pro- "before, forward, for" + emere "to obtain" (see exempt).
improper (adj.) Look up improper at
mid-15c., "not true," from French impropre (14c.), from Latin improprius, from assimilated form of in- "not, opposite of" (see in- (1)) + proprius (see proper). Meaning "not suited, unfit" is from 1560s; that of "not in accordance with good manners, modesty, decency" is from 1739. Related: Improperly (late 14c.).
impropriety (n.) Look up impropriety at
1610s, "quality or fact of being improper," from French impropriété (16c.), from Latin improprietas, from improprius (see improper). As "improper thing," 1670s.
improv (n.) Look up improv at
1970 as colloquial shortening for improvisation. The New York City comedy club, founded in 1963, was, in full, The Improvisation.
improve (v.) Look up improve at
late 15c., "to use to one's profit, to increase (income)," from Anglo-French emprouwer "to turn to profit" (late 13c.), from Old French en-, causative prefix, + prou "profit," from Latin prode "advantageous" (see proud). Spelling with -v- was rare before 17c. Meaning "to raise to a better quality or condition" first recorded 1610s. Phrase improve the occasion retains the etymological sense. Meaning "to turn land to profit" (by clearing it, erecting buildings, etc.) was in Anglo-French (13c.) and was retained in the American colonies.
improvement (n.) Look up improvement at
mid-15c., enprowment "management of something for profit," from Anglo-French emprowement, from emprouwer "turn to profit" (see improve). Meaning "betterment; amelioration" is from 1640s. Meaning "buildings, etc. on a piece of property" is from 1773. Related: Improvements.
improvidence (n.) Look up improvidence at
"lack of foresight, rashness," mid-15c., from Latin improvidentia, from assimilated form of in- "not" (see in- (1)) + providentia (see providence).
improvident (adj.) Look up improvident at
1510s, from im- "not" + provident. It retains a stronger connection with the "provide" aspect of Latin providere. Related: Improvidently.