unmentionable (adj.) Look up unmentionable at Dictionary.com
1837, from un- (1) "not" + mentionable (adj.). Humorous use of unmentionables "trousers" is attested from 1823; from 1910 as "underwear," both on notion of "articles of dress not to be mentioned in polite circles."
unmerciful (adj.) Look up unmerciful at Dictionary.com
late 15c., from un- (1) "not" + merciful (adj.). Related: Unmercifully.
unmerited (adj.) Look up unmerited at Dictionary.com
1640s, from un- (1) "not" + past participle of merit (v.).
"An ingenuous mind feels in unmerited praise the bitterest reproof. If you reject it you are unhappy, if you accept it you are undone." [Walter Savage Landor, "Imaginary Conversations"]
unmet (adj.) Look up unmet at Dictionary.com
c.1600, from un- (1) "not" + past participle of meet (v.).
unmindful (adj.) Look up unmindful at Dictionary.com
late 14c., from un- (1) "not" + mindful (adj.).
unmistakable (adj.) Look up unmistakable at Dictionary.com
1660s, from un- (1) "not" + mistake (v.) + -able. Related: Unmistakably.
unmitigated (adj.) Look up unmitigated at Dictionary.com
1590s, from un- (1) "not" + past participle of mitigate (v.).
unmodified (adj.) Look up unmodified at Dictionary.com
1792, from un- (1) "not" + past participle of modify (v.).
unmolested (adj.) Look up unmolested at Dictionary.com
1530s, from un- (1) "not" + past participle of molest (v.).
unmoor (v.) Look up unmoor at Dictionary.com
late 15c., "to free from moorings," from un- (2) "reverse, opposite of" + moor (v.). Related: Unmoored.
unmotivated (adj.) Look up unmotivated at Dictionary.com
"lacking in motivation," by 1917, from un- (1) "not" + past participle of motivate. Meaning "lacking in motive" is attested from 1871. Unmotived is from 1794.
unmounted (adj.) Look up unmounted at Dictionary.com
1590s, from un- (1) "not" + past participle of mount (v.).
unmovable (adj.) Look up unmovable at Dictionary.com
late 14c., from un- (1) "not" + movable (adj.).
unmoved (adj.) Look up unmoved at Dictionary.com
late 14c., "not affected by emotion or excitement," from un- (1) "not" + past participle of move (v.). Meaning "fixed in position" is from mid-15c.
unmuzzled (adj.) Look up unmuzzled at Dictionary.com
c.1600, from un- (1) "not" + past participle of muzzle (v.), or past participle of unmuzzle (v.), which is attested from c.1600.
unnamed (adj.) Look up unnamed at Dictionary.com
c.1500, "not mentioned by name." from un- (1) "not" + past participle of name (v.). Similar formation in Old Frisian unnamed, Middle Dutch ongenaemt.
unnatural (adj.) Look up unnatural at Dictionary.com
early 15c., "not in accord with physical nature," from un- (1) "not" + natural (adj.). Meaning "artificial" is attested from 1746; that of "at variance with moral standards" is from 1520s. Related: Unnaturally; unnaturalness.
unnecessary (adj.) Look up unnecessary at Dictionary.com
1540s, from un- (1) "not" + necessary (adj.). Related: Unnecessarily.
unneeded (adj.) Look up unneeded at Dictionary.com
1725, from un- (1) "not" + past participle of need (v.).
unnerve (v.) Look up unnerve at Dictionary.com
1620s, "to destroy the strength of," from un- (2) "reverse, opposite of" + nerve (v.). Meaning "to deprive of courage" is recorded from 1704. Related: Unnerved; unnerving.
unnoticed (adj.) Look up unnoticed at Dictionary.com
1720, from un- (1) "not" + past participle of notice (v.).
unnumbered (adj.) Look up unnumbered at Dictionary.com
late 14c., from un- (1) "not" + past participle of number (v.).
unobjectionable (adj.) Look up unobjectionable at Dictionary.com
1793, from un- (1) "not" + objectionable (adj.).
unobservant (adj.) Look up unobservant at Dictionary.com
1660s, from un- (1) "not" + observant (adj.).
unobserved (adj.) Look up unobserved at Dictionary.com
1610s, from un- (1) "not" + past participle of observe (v.).
unobstructed (adj.) Look up unobstructed at Dictionary.com
1650s, from un- (1) "not" + past participle of obstruct (v.).
unobtainable (adj.) Look up unobtainable at Dictionary.com
1775, from un- (1) "not" + obtainable (adj.). Related: Unobtainability.
unobtrusive (adj.) Look up unobtrusive at Dictionary.com
from un- (1) + obtrusive (adj.). Related: Unobtrusively; unobtrusiveness.
unoccupied (adj.) Look up unoccupied at Dictionary.com
late 14c., "idle," from un- (1) "not" + past participle of occupy (v.). In reference to ground, etc., "not possessed, not made use of," from early 15c.
unoffending (adj.) Look up unoffending at Dictionary.com
1560s, from un- (1) "not" + present participle of offend (v.).
unofficial (adj.) Look up unofficial at Dictionary.com
1798, from un- (1) "not" + official (adj.). Related: Unofficially.
unopposed (adj.) Look up unopposed at Dictionary.com
1650s, from un- (1) "not" + past participle of oppose (v.).
unorganized (adj.) Look up unorganized at Dictionary.com
1680s, from un- (1) "not" + past participle of organize (v.).
unoriginal (adj.) Look up unoriginal at Dictionary.com
1660s, "uncreated, without an origin," from un- (1) "not" + original (adj.). Meaning "derivative, second-hand" is recorded from 1774. Related: Unoriginality.
unorthodox (adj.) Look up unorthodox at Dictionary.com
1650s, from un- (1) "not" + orthodox (adj.).
unorthodoxy (n.) Look up unorthodoxy at Dictionary.com
1704, from unorthodox + -y (4).
unostentatious (adj.) Look up unostentatious at Dictionary.com
1747, from un- (1) "not" + ostentatious (adj.). Related: Unostentatiously.
unowned (adj.) Look up unowned at Dictionary.com
1610s, "unpossessed," from un- (1) "not" + past participle of own (v.). From 1715 as "unacknowledged."
unpack (v.) Look up unpack at Dictionary.com
late 15c., from un- (2) "reverse, opposite of" + pack (v.). Similar formation in Dutch ontpakken. Related: Unpacked; unpacking.
unpaid (adj.) Look up unpaid at Dictionary.com
late 14c., in reference to persons, from un- (1) "not" + past participle of pay (v.). Of debts, attested from late 15c.
unpalatable (adj.) Look up unpalatable at Dictionary.com
1680s, from un- (1) "not" + palatable (adj.). Related: Unpalatably.
unparalleled (adj.) Look up unparalleled at Dictionary.com
1590s, from un- (1) "not" + past participle of parallel (v.). Unparallel as an adjective is recorded from 1650s.
unpardonable (adj.) Look up unpardonable at Dictionary.com
1520s, from un- (1) "not" + pardonable (adj.). Related: Unpardonably.
unpatriotic (adj.) Look up unpatriotic at Dictionary.com
1775, from un- (1) "not" + patriotic.
unpaved (adj.) Look up unpaved at Dictionary.com
1530s, from un- (1) "not" + past participle of pave (v.).
unpenetrable (adj.) Look up unpenetrable at Dictionary.com
c.1400, from un- (1) "not" + penetrable (adj.). The usual word now is impenetrable.
unperceived (adj.) Look up unperceived at Dictionary.com
mid-14c., from un- (1) "not" + past participle of perceive (v.).
unpersuasive (adj.) Look up unpersuasive at Dictionary.com
1748, from un- (1) "not" + persuasive (adj.). Related: Unpersuasively.
unperturbed (adj.) Look up unperturbed at Dictionary.com
early 15c., from un- (1) "not" + past participle of perturb (v.).
unplace (v.) Look up unplace at Dictionary.com
from un- (2) "reverse, opposite of" + place (v.). Related: Unplaced; unplacing.