You searched for: “mandibles”
mandible (s) (noun), mandibles (pl)
1. The lower jaw of a vertebrate animal which is hinged to open and close the mouth and it is the only movable bone of the skull.
2. Either the upper or lower part of the beak in birds.
3. Any of various mouth organs of invertebrates (no backbones or spinal columns) used for seizing and biting food; especially, either of a pair of such organs in insects and other arthropods (creatures that have jointed legs, bodies divided into several parts, and their skeletons on the outside).
4. Etymology: "jaw, jawbone" from Late Latin mandibula, "jaw" from Latin mandere, "to chew".

Mandible is a transliteration of the Latin mandibula, "the lower jaw". The word comes from the Latin verb mandere, "to chew"; the anatomists used maxilla for both the upper and the lower jaws, and only much later did the "inferior maxilla" become the "mandible".

—Medical Meanings, A Glossary of Word Origins; William S. Haubrich, MD;
American College of Physicians; Philadelphia, 2003, page 140.

Mandible, "jaw"; especially, the lower jaw, 1392, borrowed from Old French mandible, and directly from Late Latin mandibula, from Latin mandere, "to chew", cognate with Greek mathyiai, "jaws".

—The Barnhart Dictionary of Etymology; Robert K. Barnhart, Editor;
The H.W. Wilson Company; Bronxvlle, New York; 1988; page 628.
This entry is located in the following unit: mandibulo-, mandibul-, mandibuli-; manduc-, manduca- (page 1)