floodhead has definitions from the field of geology
1
[ noun ] (geology) a wall of water rushing ahead of the flood

Examples

"we were lucky to be safe when the floodheads hit"

Used in print

(T. C. McClary, "The Flooded Desert," Argosy,...)

Out of compulsion to say something cheery , Ben_Prime blurted , `` Well , we were lucky to be on soft ground when the first floodheads hit .

Related terms

flash_flood

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