noun Cell Biology.
- a minute, narrow tubelike cell structure composed of a protein similar to actin, occurring singly and in bundles, involved in cytoplasmic movement and changes in cell shape.
noun
- thin filament, composed of the protein actin and associated proteins, that occurs abundantly in muscle and in the cytoplasm of other cells
n.
- Any of the minute fibers located throughout the cytoplasm of cells, composed of actin and functioning primarily in maintaining the structural integrity of a cell.