"Ygyn" (formed of yyn, "found, healthy"), that branch of medicine which considers health, and discovers proper means and remedies, with their use, in the preservation of that state.

The objects of this branch of medicine are, the non-naturals. See Diet, Exercise, &c.

Hygiene, more largely taken, is divided into three parts; prophylactic, which foresees and prevents diseases; synergetic, employed in preserving health; and analeptic, whose office is to cure diseases, and restore health.