fulminate v.

Proto-Indo-European root meaning "to shine, flash, burn," also "shining white" and forming words for bright colors.

It forms all or part of: beluga; Beltane; black; blancmange; blanch; blank; blanket; blaze (n.1) "bright flame, fire;" bleach; bleak; blemish; blench; blende; blend; blind; blindfold; blitzkrieg; blond; blue (adj.1); blush; conflagration; deflagration; effulgence; effulgent; flagrant; flambe; flambeau; flamboyant; flame; flamingo; flammable; Flavian; Flavius; fulgent; fulminate; inflame; inflammable; phlegm; phlegmatic; phlogiston; phlox; purblind; refulgent; riboflavin.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit bhrajate "shines;" Greek phlegein "to burn;" Latin flamma "flame," fulmen "lightning," fulgere "to shine, flash," flagrare "to burn, blaze, glow;" Old Church Slavonic belu "white;" Lithuanian balnas "pale."

c. 1600, "fulminating, thundering," from French fulminant or directly from Latin fulminantem (nominative fulminans), present participle of fulminare "to hurl lightning" (see fulminate). As a noun from 1808.

c. 1500, "act of thundering forth denunciations," from 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.