Stop! (addressed to horses). “Ho!” or “Hoa!” was formerly an exclamation commanding the knights at tournaments to cease from all further action. (See Woosh.)
“Scollers, as they read much of love, so when they once fall in love, there is no ho with them till they have their love.” —Cobler of Canterburie (1608).
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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