1
general::
1. Be ignited, as in This wood is dry enough to catch fire. [c. 1600] Also see SET ON FIRE. 2. Become inflamed with enthusiasm or passion, as in His ideas caught fire all over the country. [Early 1700s]
American Heritage Idioms
2
general::
Phrase(s): catch (on) fire
to ignite and burn with flames. • Keep your coat away from the flames, or it will catch fire. • The curtains blew against the flame of the candle and caught on fire.
McGrawhill's American Idioms And Phrasal Verbs