centriole cen·tri·ole (sěn'trē-ōl')
One of two cylindrical cellular structures composed of nine triplet microtubules and forming the mitotic astrospheres.
Either of a pair of cylinder-shaped bodies found in the centrosome of most eukaryotic organisms other than plants. During cell division (both mitosis and meiosis), the centrioles move apart to help form the spindle, which then distributes the chromosomes in the dividing cell. See more at cell, meiosis, mitosis.