Etymology
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unfamiliar (adj.)
1590s, from un- (1) "not" + familiar (adj.). Related: Unfamiliarly; unfamiliarity.
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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).
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strange (adj.)

late 13c., straunge, "from elsewhere, foreign, unknown, unfamiliar, not belonging to the place where found," from Old French estrange "foreign, alien, unusual, unfamiliar, curious; distant; inhospitable; estranged, separated" (Anglo-French estraunge, strange, straunge; Modern French étrange), from Latin extraneus "foreign, external, from without" (source also of Italian strano "strange, foreign," Spanish extraño), from extra "outside of" (see extra-). In early use also strounge. The surname Lestrange is attested from late 12c. Sense of "queer, surprising" is attested from c. 1300, also "aloof, reserved, distant; estranged." In nuclear physics, from 1956.

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unknown (adj.)
c. 1300, "strange, unfamiliar" (of persons, places), from un- (1) "not" + past participle of know (v.). Compare Old English ungecnawen. In reference to facts, "not discovered or found out," it attested from early 14c. The noun meaning "unknown person" is recorded from 1590s; the unknown "that which is unknown" is from 1650s.
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jargon (n.)
mid-14c., "unintelligible talk, gibberish; chattering, jabbering," from Old French jargon "a chattering" (of birds), also "language, speech," especially "idle talk; thieves' Latin" (12c.). Ultimately of echoic origin (compare Latin garrire "to chatter").

From 1640s as "mixed speech, pigin;" 1650s as "phraseology peculiar to a sect or profession," hence "mode of speech full of unfamiliar terms." Middle English also had it as a verb, jargounen "to chatter" (late 14c.), from French.
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disaccustom (v.)

late 15c., "render a thing no longer customary" (a sense now obsolete); 1520s in modern sense "render (a person) unaccustomed to (something), cause to lose (a habit) by disuse," from Old French desacostumer "render unfamiliar" (Modern French désaccoutumer), from des- "not, opposite of" (see dis-) + acostumer "become accustomed, bring into use" (see accustom). Discustom (c. 1500) also was used. Related: Disaccustomed.

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civics (n.)

"the science of government, study of the rights and responsibilities of a citizen," 1885, in American Institute of Civics, incorporated May 1885, from civic, by analogy with politics (see -ics).

"The term 'Civics,' however unfamiliar the word, could be wisely applied with a broader significance than that attached to 'Political Science,' as including not only the science of government, but political economy, and that part of social science which is related to government and citizenship." [E.E. White, quoted in The School Journal, July 25, 1885]
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uncouth (adj.)
Old English uncuð "unknown, strange, unusual; uncertain, unfamiliar; unfriendly, unkind, rough," from un- (1) "not" + cuð "known, well-known," past participle of cunnan "to know" (see can (v.1)), from PIE root *gno- "to know." Meaning "strange, crude, clumsy" is first recorded 1510s. The compound (and the thing it describes) widespread in IE languages, such as Latin ignorantem, Old Norse ukuðr, Gothic unkunþs, Sanskrit ajnatah, Armenian ancanaut', Greek agnotos, Old Irish ingnad "unknown."
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fremd (adj.)

Northern English and Scottish survival of Middle English fremed "foreign; remote; unfamiliar; not related; unheard-of; unfriendly, distant and formal;" as a noun, "a stranger," from Old English fremde (Northumbrian fremþe); cognate with Old Saxon fremithi, Old Frisian fremed, Dutch vreemd, Old High German framidi, German fremd, Gothic framaþs "strange, foreign." In the Old English glossaries, fremde glosses Latin exter, alienus.

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chill (v.)

late 14c., intransitive, "to feel cold, grow cold;" c. 1400, transitive, "to make cold," from chill (n.). Related: Chilled; chilling; chillingly. Figurative use "discourage, dispirit" is from late 14c. Meaning "hang out" first recorded 1985; from earlier chill out "relax" (1979).

Sheila E. sizzles in the new flick, Krush Groove, but some New York critics couldn't groove with it because many of the terms are unfamiliar to them. Examples: breakin' out (slang for leaving), chill (for cool down) and death (for something that's really good). [Jet, Nov. 11, 1985]
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