A: Nothing more than pure fiction.
The “intercostal clavicle” is a fictitious bone created by the screenwriters of the movie “Bringing up Baby,” staring Cary Grant and Katharine Hepburn. In the movie Cary Grant’s character, Dr. David Huxley, needs the “intercostal clavicle” to complete a dinosaur skeleton he was building at his museum.
In reality, the two separate words by themselves are real anatomical terms. Intercostal means “between ribs” and can be used to describe structures found between the ribs (intercostal arteries, sixth intercostal space, internal intercostal muscle, etc). The clavicle is a real bone found in some animals extending from the first rib to the shoulder to connect the forearm to the thorax. However, the combination of these two terms is nonsensical, seing as they are anatomically miles apart from one another.