- unevitable (adj.)
- from un- (1) "not" + evitable. The usual word is inevitable. Related: Unevitably.
- unexamined (adj.)
- late 15c., from un- (1) "not" + past participle of examine (v.).
- unexceptionable (adj.)
- 1660s, from un- (1) "not" + exceptionable.
- unexceptional (adj.)
- from un- (1) "not" + exceptional (adj.).
- unexcusable (adj.)
- late 14c., from un- (1) "not" + excusable. The usual word is inexcusable. Related: Unexcusably.
- unexpected (adj.)
- 1580s, from un- (1) "not" + past participle of expect (v.). Related: Unexpectedly.
- unexperienced (adj.)
- 1560s, from un- (1) "not" + past participle of experience (v.).
- unexplainable (adj.)
- 1711, from un- (1) "not" + explain + -able. Related: Unexplainably.
- unexplained (adj.)
- 1721, from un- (1) "not" + past participle of explain (v.).
- unexplored (adj.)
- 1690s, from un- (1) "not" + past participle of explore (v.).
- unexpurgated (adj.)
- 1882, from un- (1) "not" + past participle of expurgate (v.).
- unfading (adj.)
- from un- (1) "not" + past participle of fade (v.).
- unfailing (adj.)
- late 14c., "never coming to an end, unceasing, everlasting, inexhaustible," from un- (1) "not" + present participle of fail (v.). Related: Unfailingly.
- unfair (adj.)
- Old English unfægr "unlovely, not beautiful, deformed, hideous, unlovable," from un- (1) "not" + fair (adj.). Similar formation in Old Norse ufagr, Gothic unfagrs. Meaning "wicked, evil, bad" is recorded from c. 1300. Sense of "not equitable, unjust" is first recorded 1713. Related: Unfairly.
- unfairness (n.)
- Old English unfægernes "ugliness, disfigurement;" see unfair + -ness.
- unfaithful (adj.)
- mid-14c., "acting falsely," from un- (1) "not" + faithful. In Middle English it also had a sense of "infidel, unbelieving, irreligious" (late 14c.). Sense of "not faithful in marriage" is attested from 1828. Related: Unfaithfully; unfaithfulness.
- unfaltering (adj.)
- 1660s, from un- (1) "not" + present participle of falter (v.). Related: Unfalteringly.
- unfamiliar (adj.)
- 1590s, from un- (1) "not" + familiar (adj.). Related: Unfamiliarly; unfamiliarity.
- unfamous (adj.)
- late 14c., "not well known, obscure," from un- (1) "not" + famous (adj.). Also from late 14c. as "notably bad," a sense now in infamous.
- unfashionable (adj.)
- 1560s, "incapable of being shaped," from un- (1) "not" + fashionable. Meaning "not in accordance with prevailing fashion" is attested from 1640s. Related: Unfashionably.
- unfasten (v.)
- early 13c., from un- (2) "opposite of" + fasten. Old English had unfæstnian "to unfasten." Related: Unfastened; unfastening.
- unfathomable (adj.)
- 1610s, originally in the figurative sense, of feelings, conditions, etc., from un- (1) "not" + fathomable. Literal sense attested from 1670s. Related: Unfathomably.
- unfathomed (adj.)
- 1620s, from un- (1) "not" + past participle of fathom (v.).
- unfavorable (adj.)
- also unfavourable, mid-15c. (implied in unfavorably), from un- (1) "not" + favorable (adj.).
"We must not indulge in unfavorable views of mankind, since by doing it we make bad men believe that they are no worse than others, and we teach the good that they are good in vain." [Walter Savage Landor, "Imaginary Conversations"]
- unfazed (adj.)
- 1933, American English, from un- (1) "not" + past participle of faze (v.).
- unfeasible (adj.)
- 1520s, from un- (1) "not" + feasible.
- unfeeling (adj.)
- late Old English had unfelende, "having no sensation." Middle English had a verb unfeel "be insensible, fail to feel" (early 14c.) as well as unfeelingness "insensibility, loss of sensation," and unfeelingly "without understanding or direct knowledge" (late 14c.), and a verbal noun unfeeling "loss of sensation, lack of feeling." However the word in its main modern meaning "devoid of kindly or tender feelings" is from 1590s, from un- (1) "not" + past participle of feel (v.). Related: Unfeelingly.
- unfeigned (adj.)
- late 14c., "sincere, genuine, true, real," from un- (1) "not" + past participle of feign (v.).
- unfelt (adj.)
- 1580s, from un- (1) "not" + past participle of feel (v.).
- unfetter (v.)
- mid-14c., from un- (2) "opposite of" + fetter (v.). The figurative sense is recorded from late 14c. Related: Unfettered; unfettering.
- unfinished (adj.)
- 1550s, from un- (1) "not" + past participle of finish (v.).
- unfit (adj.)
- 1540s, "not suitable" (in reference to things), from un- (1) "not" + fit (adj.). Related: Unfitness. In reference to persons or human qualities, attested from 1550s.
- unfit (v.)
- "to render unfit," 1610s, from unfit (adj.), or else from un- (2) "reverse of" + fit (v.). Related: Unfitted; unfitting.
- unflagging (adj.)
- 1715, from un- (1) "not" + present participle of flag (v.). Related: Unflaggingly.
- unflappable (adj.)
- 1958, from un- (1) "not" + flap (v.) + -able. Originally used in reference to Harold Macmillan, British P.M. 1957-63.
- unflattering (adj.)
- 1580s, from un- (1) "not" + gerundive of flatter. Related: Unflatteringly.
- unfledged (adj.)
- c. 1600, of persons, "immature, not experienced," from un- (1) "not" + past participle of fledge (v.). Literal sense of "not yet covered in feathers" is recorded from 1610s.
- unflinching (adj.)
- 1728, from un- (1) "not" + present participle adjective of flinch (v.). Related: Unflinchingly.
- unfold (v.)
- Old English unfealdan, "to open or unwrap the folds of," also figuratively, "to disclose, reveal, explain," from un- (2) "opposite of" + fold (v.). Similar formation in Middle Dutch ontvouden, German entfalten. Intransitive sense is attested from late 14c. Related: Unfolded; unfolding.
- unforced (adj.)
- 1590s, from un- (1) "not" + past participle of force (v.).
- unforeseeable (adj.)
- 1670s, from un- (1) "not" + foreseeable (see foresee). Related: Unforeseeably.
- unforeseen (adj.)
- late 14c., from un- (1) "not" + past participle of foresee. Similar formation in Middle Dutch onvoresien, Dutch onvoorzien, Middle High German unvorsen.
- unforgettable (adj.)
- 1806, from un- (1) "not" + forgettable. Related: Unforgettably.
- unforgivable (adj.)
- 1540s, from un- (1) "not" + forgivable. In early use, especially with reference to the sin described in Matt. xii:31. Related: Unforgivably.
- unforgiven (adj.)
- early 15c., from un- (1) "not" + past participle adjective from forgive (v.). Old English had unforgifen.
- unforgiving (adj.)
- 1713, from un- (1) "not" + present participle adjective from forgive. Old English had unforgifende.
- unforgotten (adj.)
- 1670s, from un- (1) "not" + forgotten. Similar formation in German unvergessen.
- unformed (adj.)
- early 14c., from un- (1) "not" + past participle adjective from form (v.).
- unfortunate (adj.)
- mid-15c., "unlucky," from un- (1) "not" + fortunate (adj.). Infortunate in same sense is older. In late 18c.-early 19c., unfortunate woman was a polite way to say "prostitute." The noun meaning "one who is not fortunate" is recorded from 1630s.
- unfortunately (adv.)
- 1540s, "in an unfortunate manner, by ill-fortune," from unfortunate + -ly (2). The original meaning is now rare; the main modern sense of "sad to say, unhappily, unluckily," in parenthetical use, is recorded from 1770s.
