Engastrimythi

Engastrimythi (Gr. ἐν, in, γαστήρ, the belly, and μῦθος, an utterance), a name given to the priestesses of Apollo, from a species of ventriloquism which they practiced, speaking from within, while not the slightest motion of the lips could be observed. The voice was supposed to proceed from a spirit within the body of the Pythoness (q.v.).