1. a worthless or vicious animal, especially a horse; a sorry hack (obsolete)
2. a contemptible, worthless person; a mean, base, cowardly fellow; a wretch (archaic)
3. a disreputable slut, a wanton (archaic)
4. the sediment of beer, lees, dregs: usually plural (dialect)
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A late word, of obscure etymology: perhaps from hield hyld vb., to bend downwards, bow, also to fall, sink, and to decline, turn waywardly aside + -ing. It is not clear whether the application was first to a horse or to a human being.
From: The Dramatick Works of John Dryden
Volume the Fifth, 1735
Troilus and Cressida: Or, Truth Found Too Late. A Tragedy.
Act III. Scene II. P. 76