[rap.id] adj [L rapidus seizing, sweeping, rapid, fr. rapere to seize, sweep away; akin to Lith aprepti to embrace] (1634): marked by a fast rate of motion, activity, succession, or occurrence syn see fast -- rap.id.ly adv -- rap.id.ness n
[2]rapid n (1765): a part of a river where the current is fast and the surface is usu. broken by obstructions--usu. used in pl. but sing. or pl. in constr.