a. (Anat. & Zool.) Situated below the costas, or ribs; as, the subcostal muscles. [ 1913 Webster ]

☞ The subcostal muscles are distinct from, and within, the intercostal. [ 1913 Webster ]

n. 1. (Anat.) A subcostal muscle. [ 1913 Webster ]

2. (Zool.) One of the principal nervures of the wings of an insect. It is situated next beneath or behind the costal. See Nervure. [ 1913 Webster ]