[grav.i.ta.tion] n (ca. 1645) 1: a force manifested by acceleration toward each other of two free material particles or bodies or of radiant-energy quanta: gravity 3a(2)
2: the action or process of gravitating -- grav.i.ta.tion.al adj -- grav.i.ta.tion.al.ly adv -- grav.i.ta.tive adj