Arm bone is a term commonly used to describe the humerus, which is the upper arm bone. However, there are several other terms that can be used to refer to the arm bone depending on the context. For instance, the ulna and radius are two bones located in the forearm that can also be referred to as arm bones. Other synonyms include upper limb bone or brachial bone, which refers to any bone in the arm region. The scapula or shoulder blade is another bone that is connected to the arm bone and can be considered part of the arm bone complex. In summary, while the humerus is the most common arm bone, several other bones can also be referred to as arm bones depending on the context.