fou·droy·ant (f-droiənt, f′drwä-yäɴ)
1. Dazzling or stunning in effect.
2. Medicine Occurring suddenly and severely. Used of a disease.
[French, from present participle of foudroyer, to strike with lightning, from foudre, lightning, from Old French fouldre, from Latin fulgur, from fulgēre, to flash; see bhel-1 in the Appendix of Indo-European roots.]
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