英语词源字典 - 在线词源网站

unmotivated (adj.)[unmotivated 词源字典]: "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.[unmotivated etymology, unmotivated origin, 英语词源]
unmounted (adj.): 1590s, from un- (1) "not" + past participle of mount (v.).
unmovable (adj.): late 14c., from un- (1) "not" + movable (adj.).
unmoved (adj.): 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.): 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.): 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.): 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.): 1540s, from un- (1) "not" + necessary (adj.). Related: Unnecessarily.
unneeded (adj.): 1725, from un- (1) "not" + past participle of need (v.).
unnerve (v.): 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.): 1720, from un- (1) "not" + past participle of notice (v.).
unnumbered (adj.): late 14c., from un- (1) "not" + past participle of number (v.).
unobjectionable (adj.): 1793, from un- (1) "not" + objectionable (adj.).
unobservant (adj.): 1660s, from un- (1) "not" + observant (adj.).
unobserved (adj.): 1610s, from un- (1) "not" + past participle of observe (v.).
unobstructed (adj.): 1650s, from un- (1) "not" + past participle of obstruct (v.).
unobtainable (adj.): 1775, from un- (1) "not" + obtainable (adj.). Related: Unobtainability.
unobtrusive (adj.): from un- (1) + obtrusive (adj.). Related: Unobtrusively; unobtrusiveness.
unoccupied (adj.): 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.): 1560s, from un- (1) "not" + present participle of offend (v.).