I. |stər(ˌ)nō|klīdə|maˌstȯid adjective
Etymology: New Latin sternocleidomastoides, from stern- + cleid- + mastoides mastoid
: of, relating to, or constituting a thick superficial muscle on each side arising by one head from the first segment of the sternum and a second from the inner part of the clavicle and inserted into the mastoid and occipital bone
II. noun
: a sternocleidomastoid muscle