What term describes the portion of the muscle that is attached to bone and assists in movement?

The term that describes the portion of a muscle that is attached to bone and assists in movement is referred to as the insertion. In anatomical terms, the insertion of a muscle is the point where the muscle attaches to the bone that it moves. When a muscle contracts, the insertion moves toward the origin, which is the fixed attachment point of the muscle. This movement facilitated by the muscle's insertion is crucial for various bodily movements and functions.

In this context, understanding the anatomy and function of muscles can help in recognizing how muscles work together to produce movement. The belly, though related to the muscle structure, refers to the thick, central part of the muscle itself, not its attachment. Vibration does not pertain to muscle attachment, and friction is a physical force that occurs as muscles move but is not related to the anatomical terms of muscle attachments.