Английский Этимологический словарь - flame (n.)

- c.1303, from Anglo-Fr. flaume, from O.Fr. flamme, from L. flammula "small flame," dim. of flamma "flame," from PIE *bhleg-/*phleg-. The meaning "a sweetheart" is attested from 1647; the verb sense of "unleash invective on a computer network" is from 1980s. Flamer, flaming in homosexual slang date from 1970s; flaming as an intensifying adj. dates from late 19c.