vail that vail might: whatever happens; come what may. [After Anglo-Norman vaille qe vailler purra and Middle French vaille que vaille (see vail que vailphr.).]
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the world > existence and causation > occurrence > future events > [phrase] > whatever may happen
sink or swimc1410
vail that vail mightc1475
a1500 Partenay (Trin. Cambr.) l. 2672Vail that vail might, the monkys brend so.