muscles of eyeball pl.n.
The muscles within the eye socket, comprising the four rectus muscles, the two oblique muscles, and the elevator muscle of the upper eyelid.
- Muscles of mastication
muscles of mastication pl.n. The masseter, temporal, lateral pterygoid, and medial pterygoid muscles considered as a group.
- Muscles of head
muscles of head pl.n. The muscles of facial expression, mastication, and the suboccipital muscles considered as a group.
- Muscle spasm
muscle spasm n. Persistent increased tension and shortness in a muscle or group of muscles that cannot be released voluntarily.
noun 1. Cell Biology. a proprioceptor in skeletal muscle, composed of striated muscle fibers and sensory nerve endings in a connective tissue sheath, that conveys information via the spinal nerves on the state of muscle stretch, important in the reflex mechanism that maintains body posture. muscle spindle n. A stretch receptor found in vertebrate muscle.