A florid style which prevailed in France in the 15th and 16th centuries. So called from its flame-like tracery.
“The great tower [of Antwerp cathedral] ... most florid and flamboyant ... is one of the few rivals of the peerless steeple of Strasbourg.” —James: Sketches (Belgium), p. 394.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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