英语词源字典 - 在线词源网站

unaccented (adj.)[unaccented 词源字典]: 1590s, from un- (1) "not" + past participle of accent (v.).[unaccented etymology, unaccented origin, 英语词源]
unacceptable (adj.): late 15c., from un- (1) "not" + acceptable. Related: Unacceptably.
unaccompanied (adj.): 1540s, "not in the company of others, having no companions," from un- (1) "not" + past participle of accompany (v.). Musical sense "without instrumental accompaniment" is first recorded 1818.
unaccomplished (adj.): 1520s, "not finished," from un- (1) "not" + past participle of accomplish (v.). Meaning "not furnished with social or intellectual accomplishments" is from 1729 (see accomplished).
unaccountable (adj.): 1640s, "inexplicable," from un- (1) "not" + accountable. Meaning "not liable to be called to account" is recorded from 1640s. Related: Unaccountably; unaccountability; unaccountableness.
unaccredited (adj.): 1828, from un- (1) "not" + accredited.
unaccustomed (adj.): 1520s, "not customary, unfamiliar," from un- (1) "not" + past participle of accustom (v.). Meaning "not accustomed or habituated" (to) is first attested 1610s (see accustomed).
unacknowledged (adj.): 1580s, from un- (1) "not" + past participle of acknowledge (v.).
unacquainted (adj.): 1520s, from un- (1) "not" + past participle of acquaint (v.).
unadorned (adj.): 1630s, from un- (1) "not" + past participle of adorn (v.).
unadulterated (adj.): 1719, from un- (1) "not" + past participle of adulterate (v.).
unadvertised (adj.): mid-15c., "uninformed, unadvised," from un- (1) + advertised. Sense of "not announced or made known" is from 1864.
unaffected (adj.): 1580s, "not influenced, untouched in mind or feeling," from un- (1) "not" + past participle of affect (v.). Meaning "not adopted or assumed, genuine" is recorded from 1590s; that of "not acted upon or altered (by something)" is first attested 1830. Related: Unaffectedly; unaffectedness.
unafraid (adj.): early 15c., from un- (1) "not" + afraid.
unaided (adj.): 1660s, from un- (1) "not" + past participle of aid (v.).
unalienable (adj.): 1610s, from un- (1) "not" + alienable. Related: Unalienably.
unalloyed (adj.): 1670s (figurative); 1760s (literal), from un- (1) "not" + past participle of alloy (v.).
unalterable (adj.): 1610s, from un- (1) "not" + alterable. Related: Unalterably.
He reach'd a middle height, and at the stars,
Which are the brain of heaven, he look'd, and sank.
Around the ancient track march'd, rank on rank,
The army of unalterable law.

[George Meredith, "Lucifer in Starlight"]
unaltered (adj.): 1550s, from un- (1) "not" + past participle of alter (v.).
unambiguous (adj.): 1630s, from un- (1) "not" + ambiguous. Related: Unambiguously; unambiguousness.