cytoskeleton cy·to·skel·e·ton (sī'tə-skěl'ĭ-tn)
The internal framework of a cell, composed largely of actin filaments and microtubules.
The internal framework of a cell, composed of a network of protein filaments and extending throughout the fluid of the cell (the cytosol). The cytoskeleton consists mainly of actin filaments and microtubules and plays an important role in cell movement, shape, growth, division, and differentiation, as well as in the movement of organelles within the cell. All eukaryotic cells have a cytoskeleton.