the.com/flush

means To flow or push with a sudden rush of liquid, to glow red in the face, or to hold a hand of cards all of the same suit — depending entirely on context.

from A tangle of meanings that may share more than one root. The 'rush of water' sense likely comes from Middle English 'flusshen,' to fly up suddenly (think birds flushed from cover), possibly blended with 'flash' and 'gush.' The card-game 'flush' is a separate stream, arriving via French 'flux' or Latin 'fluxus,' a flowing — a run of cards flowing together. The reddening face borrows the same imagery of blood rushing in. Whether these currents truly spring from one source or just pooled together over centuries is genuinely murky — etymologists keep the channels somewhat separate.