- The entrance into a canal or hollow organ, such as the vagina.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Examples from the Web for introitus
The Kyrie is preceded by the Introitus, beginning with a prayer for the departed.Life Of Mozart, Vol. 3 (of 3)
Francesco stood before the high altar among the monks and acolytes and read the Introitus aloud in steady tones.The Hill of Venus
A very old priest, whose features Tristan could not distinguish, began to chant the Introitus, in deep long drawn notes.Under the Witches' Moon