A muscle fiber, also spelled muscle fibre (see spelling differences), also technically known as a myocyte, is a single cell of a muscle. Muscle fibers contain many myofibrils, the contractile unit of muscles. Muscle fibres are very long; a single fibre can reach a length of 30cm.Muscle fibres can be grouped according to what kind of tissue they are found in -- skeletal muscle, smooth muscle, and cardiac muscle. The muscle cells of heart muscle tissue are called cardiomyocytes.
See more at Wikipedia.org...
Noun 1. an elongated contractile cell that forms the muscles of the body (synonym) muscle fiber, muscle fibre (hypernym) somatic cell, vegetative cell (hyponym) striated muscle cell, striated muscle fiber (part-holonym) muscle, musculus