What does "ho" mean?

Ho: Halloo! attend! -- a call to excite attention, or to give notice of approach. "What noise there, ho" Shak. "Ho! who's within" Shak.

Additional senses

  1. 2.Etym: [Perhaps corrupted fr. hold; but cf. F. hau stop! and E. whoa.] Stop! stand still! hold! -- a word now used by teamsters, but formerly to order the cessation of anything. [Written also whoa, and, formerly, hoo.] The duke . . . pulled out his sword and cried "Hoo!" Chaucer. An herald on a scaffold made an hoo. Chaucer.

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