intercostal

American Heritage® Dictionary of the English Language, Fourth Edition

1. adj. Located or occurring between the ribs.
2. n. A space, muscle, or part situated between the ribs.

Century Dictionary and Cyclopedia

1. Situated or intervening between successive ribs of the same side of the body: as, intercostal muscles, vessels, spaces.
2. n. An intercostal structure, as an artery, and especially a muscle; an intercostalis. The intercostals are two layers of muscular fibers occupying the intercostal spaces, running obliquely, and for the most part between any two successive ribs. They are respiratory in function.
3. In iron ship-building, noting a structural member composed of a number of short pieces fitted in the spaces between a series of other continuous structural members which it crosses: as, an intercostal floorplate, one in which the floor is in short pieces between the longitudinals; an intercostal keelson, intercostal longitudinal, one in short pieces between the frames; an intercostal angle-bar, intercostal seam-strap, one in short pieces between frames or deck-beams, etc.

Wiktionary

1. adj. anatomy Between the ribs of an animal or person.
2. adj. nautical Between the ribs of a boat.
3. n. anatomy The intercostal muscles.
4. n. anatomy Something that is between the ribs of an animal.
5. n. nautical Hull reinforcing inserted between frames or bulkheads of a boat.

GNU Webster's 1913

1. adj. (Anat. & Physiol.) Between the ribs; pertaining to, or produced by, the parts between the ribs.

WordNet 3.0

1. n. muscles between the ribs; they contract during inspiration
2. adj. located or occurring between the ribs