Hálloo. interj. [The original of this word is controverted: some imagine it corrupted from a lui, to him! others from allons, let us go! and Skinner from haller, to draw.] A word of encouragement when dogs are let loose on their game.

            Some popular chief,
More noisy than the rest, but cries halloo,
And, in a trice, the bellowing herd come out. Dryden.