What does mandible mean?
A mandible is the lower jawbone in humans and other vertebrates. It forms the lower portion of the skull, supports the lower teeth, and moves at the temporomandibular joint to bring the lower teeth into contact with the upper teeth during biting and chewing. In clinical and anatomical writing, the term is more precise than the general word “jaw” because it identifies a specific skeletal structure. In zoology, “mandible” also names the paired appendages found around the mouths of insects, crustaceans, spiders, and other arthropods. These structures are commonly adapted to biting, cutting, scraping, or gripping food rather than functioning as hinged jawbones. The word is especially useful in medicine, dentistry, developmental biology, and comparative anatomy, where distinctions between the lower jaw, upper jaw, and similar structures in different animal groups matter. Although “jawbone” is more familiar in general speech, “mandible” is the appropriate specialist term in technical contexts.
nounThe lower jawbone of a vertebrate, forming the lower part of the skull and moving against the upper jaw. In arthropods, a mandible is one of the paired appendages used to grasp and manipulate food.
- The lower jawbone of a vertebrate.
- Either of the paired mouthparts of an arthropod, used in feeding and handling objects.
"The surgeon carefully repositioned the fractured lower mandible."
"The mandible supports the lower teeth and enables the mouth to close."
"The beetle uses its sharp mandibles to cut through the plant stem."
The plural is used for multiple jawbones or arthropod mouthparts, especially when describing animals with paired structures.
"The insect moved its mandibles rapidly through the decaying wood."
A mandible has a bite to lose: it is the jawbone that turns chewing into a bite.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does mandible come from?
The English word comes from Latin mandibula, meaning “jaw,” a form related to mandere, “to chew.” Latin mandibula was adopted into English in the 16th century and initially referred broadly to the jaw or jawbone. Modern usage distinguishes the lower jaw in vertebrate anatomy while also applying the term to the mouthparts of arthropods.
Related word forms
How mandible is actually used
In human anatomy, the term is chiefly used in specialist contexts such as dentistry, surgery, and forensic medicine. In zoology, it refers to the mouthparts of arthropods and may denote either member of a functional pair, even though the corresponding structures are not always anatomically upper and lower jaws.
Easily confused with mandible
The mandible is the lower jaw, whereas the maxilla is the upper jaw or upper jawbone in vertebrates.
A mandible can also refer to an arthropod's paired mouthpart, a usage that does not necessarily imply a bone.