microtubule mi·cro·tu·bule (mī'krō-tōō'byōōl, -tyōō-)
Any of the proteinaceous cylindrical hollow structures that are distributed throughout the cytoplasm of eukaryotic cells, providing structural support and assisting in cellular locomotion and transport.
|microtubule (mī'krō-t'byl) Pronunciation Key
Any of the tube-shaped protein structures that help eukaryotic cells maintain their shape and assist in forming the cell spindle during cell division. Microtubules and actin filaments are the main components of the cell's supporting matrix or cytoskeleton.