Musculocutaneous is a word that refers to a nerve that innervates the arm muscles and skin. However, there are several synonyms for this word that can be used interchangeably in certain contexts. Some of these synonyms include brachial, radial, and ulnar nerves. The brachial nerve refers to the major nerve that extends from the neck to the elbow, while the radial nerve is a nerve that runs down the arm to the wrist. The ulnar nerve is another nerve that innervates the arm and is responsible for sensation in the fingers. Although these words are different in meaning, they can all be used to describe the musculocutaneous nerve in certain contexts.