Flammable
来自Big Physics
early 19th century: from Latin flammare, from flamma ‘a flame’.
wiktionary
Back-formation from inflammable, which is used to avoid confusion with non-flammable, as the prefix in- is often used to mean "un-; non-", although it was originally meant in a sense closely related to en-.
etymonline
flammable (adj.)
1813, from stem of Latin flammare "to set on fire" (from flamma "flame, blazing fire;" see flame (n.)) + -able. In modern (20c.) use, a way to distinguish from the ambiguity of inflammable.
