Based on the Random House Dictionary, © Random House, Inc. 2015.
Foreigners and any young people dressed in alternative-looking clothing made sure to clear out of the streets before they arrived.
late 13c. "bright," from Old French cler "clear" (of sight and hearing), "light, bright, shining; sparse" (12c. Modern French clair ), from Latin clarus "clear, loud," of sounds; figuratively "manifest, plain, evident," in transferred use, of sights, "bright, distinct;" also "illustrious, famous, glorious" (source of Italian chiaro. Spanish claro ), from PIE *kle-ro-. from root *kele- (2) "to shout" (see claim (v.)).
late 14c. "to fill with light," from clear (adj.). Of weather, from late 14c. Meaning "make clear in the mind" is mid-15c. as is sense of "to remove
what clouds." Meaning "to prove innocent" is from late 15c. Meaning "get rid of" is from 1530s.
Meaning "to free from entanglement" is from 1590s; that of "pass without entanglement" is from 1630s. Meaning "to leap clear over" is first attested 1791. Meaning "get approval for" (a proposal, etc.) is from 1944; meaning "establish as suitable for national security work" is from 1948. Related: Cleared ; clearing.
To clear (one's) throat is from 1881; earlier clear (one's) voice (1701). To clear out "depart, leave" (1825), perhaps is from the notion of ships satisfying customs, harbor regulations, etc. then setting sail. To clear up is from 1620s, of weather; 1690s as "make clear to the mind." Clear the decks is what is done on a ship before it moves.