Anat. [mod.L. subclāvius (sc. musculus, f. sub- SUB- 1 b + clāvis key (cf. CLAVICLE1 etym.).] In full subclavius muscle: A small muscle extending from the first rib to the clavicle.
1704. J. Harris, Lex. Techn., I. Subclavius, is a Muscle of the Thorax.
1733. trans. Winslows Anat. (1756), I. 288. The Subclavius is a proper Depressor of the Clavicula.
1831. Knox, Cloquets Anat., 31. Its anterior extremity [sc. of the first rib] sometimes affords insertion above to the sub-clavius muscle.
18356. Todds Cycl. Anat., I. 360/1. The thickened edge of the fascia which covers the subclavius.