1. Preparation of the natural crown of a tooth by removal of part or all of the natural structure and replacing the prepared surfaces with a veneer of suitable dental material (gold or nonprecious metal casting, porcelain, plastic, or combinations).
2. That stage of childbirth when the fetal head has negotiated the pelvic outlet and the largest diameter of the head is encircled by the vulvar ring.
Stedman’s Medical Dictionary © Wolters Kluwer Health. All rights reserved.