Occipitalis

Part of speech: noun

Pronunciation: /ɑkˌsɪp.əˈteɪ.lɪs/

Definitions

1. The muscle found at the posterior of the head functions to facilitate scalp mobility and plays a role in facial expressions
2. Located at the back of the skull, this muscle aids in the movement of the scalp and is involved in the dynamics of facial expression
3. A muscle situated at the rear of the head that assists in scalp movement and contributes to facial expression dynamics

Etymology: The occipital muscle is named for the occiput, the bony back of the skull, and the Latin "occiput" itself combines "ob-" (against, toward) with "caput" (head), so the name literally points to the part of the head that faces away from the viewer. The adjective "occipitalis" was built from that noun, and the anatomical phrase "mūsculus occipitālis" was later shortened in New Latin to "occipitalis" alone, leaving the adjective to stand for the whole muscle. English took this shortened form directly, without adapting it, which is why it looks and sounds so much like the Latin. It is a doublet of "occipital", the adjective that describes the back of the head, so the two words share a root but reached English along different routes: one as an everyday descriptive term, the other as a technical anatomical noun.