Word Origin & History
flaremid-16c., originally "spread out" (hair), of unknown origin, perhaps from Du. vlederen. Related: Flared; flaring. The noun meaning "bright, unsteady light" is 1814, from the verb, which led to the sense of "signal fire" (1883). The notion of "spreading out in display" is behind the notion of "spreading
EXPANDgradually outward" (1640s). Flare-up "a sudden burst" is from 1837. Flares "flared trousers" is from 1964.
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