early 15c., "publish a 'thundering' denunciation; hurl condemnation (at an offender)," a figurative use, from Latin fulminatus, past participle of fulminare "hurl lightning, lighten," figuratively "to thunder," from fulmen (genitive fulminis) "lightning flash," related to fulgor "lightning," fulgere "to shine, flash," from PIE *bhleg- "to shine, flash," from root *bhel- (1) "to shine, flash, burn." Metaphoric sense (the oldest in English) in reference to formal condemnation is from Medieval Latin fulminare, used of formal ecclesiastical censures. Related: Fulminated; fulminating.

c. 1500, "act of thundering forth denunciations," from Middle French fulmination, from Latin fulminationem (nominative fulminatio) "a discharge of lightning," noun of action from past-participle stem of fulminare "to hurl lightning" (see fulminate). Literal sense "act of exploding or detonating" (1620s) is rare in English.

late 14c., "vapor, odorous vapor; exhalation," from Old French fum "smoke, steam, vapor, breath, aroma, scent" (12c.), from Latin fumus "smoke, steam, fume, old flavor" (source also of Italian fumo, Spanish humo), from PIE root *dheu- (1) "dust, vapor, smoke."

In old medicine, an "exhalation" of the body that produces emotions, dreams, sloth, etc; later especially of smokes or vapors that go to the head and affect the senses with a narcotic or stifling quality.

c. 1400, "to fumigate" (transitive), from Old French fumer "to smoke, burn" (12c.), from Latin fumare "to smoke, steam," from fumus "smoke, steam, fume" (from PIE root *dheu- (1) "dust, vapor, smoke"). Intransitive meaning "throw off smoke, emit vapor" is from 1530s; the figurative sense "show anger, be irritated" is slightly earlier (1520s). Related: Fumed; fumes; fuming.