myofibril

[ mahy-uh-fahy-bruhl, -fib-ruhl ]

noun

, Cell Biology.

1. a contractile fibril of skeletal muscle, composed mainly of actin and myosin.

Word History and Origins

Origin of myofibril¹

First recorded in 1895–1900; myo- + fibril

Example Sentences

Our bodies rebuild these tears by adding either sarcomeres, which are fibrous proteins inside muscle cells, or myofibrils—chains of rod-like units also in muscle cells that give them their striped appearance.

From Popular-Science