muscle-bound

The term is a modern English compound, first appearing in the late 19th century. It literally describes a state where one's muscles are figuratively "tied up" or "bound," leading to stiffness and a lack of suppleness. The first element, "muscle," originates from the Latin musculus (little mouse), a diminutive of mus, due to the perceived resemblance of a flexing muscle to a mouse moving under the skin. The second element, "bound," derives from the Old English verb bindan, carrying the sense of being constrained or made fast. The word's logic perfectly captures the condition: overdeveloped muscles restrict free movement, and this physical sense was later extended metaphorically to describe rigid, unyielding attitudes or systems.

Structure: muscle (body tissue) + bound (restricted) - muscle: From Latin musculus (little mouse, muscle), via Old French. In this compound, it refers to the body tissue. - bound: From Old English bindan (to tie). In this compound, it functions as an adjective-forming element meaning "confined, restricted, or destined."