Irritability
in anatomy, vital contractibility, the property of visibly contracting even after death, on the application of plication of a stimulus. The right auricle has been found irritable for 16½ hours after death. A voluntary muscle has been found irritable 24 hours after death.
In botany, excitability of an extreme character, in which an organ exhibits movements different from those commonly met with in plants. Its known causes are three-atmospheric pressure, spontaneous motion, and the contact of other bodies. Thus plants sleep, the compound leaves, where such exist, folding together; so also the sensitive plant shrinks from touch.