quadruple

i. & t. [Fr. quadrupler, from Lat. quadruplo =to multiply by four, from quadru plus quadruple (q.v.).] A. In trans.: To become fourfold as much or as many; to increase fourfold. "It has probably, on the average, quadrupled. " --Ma caulay: Hist. Eng., ch. iii. B. Trans.: To make four times as much or as many; to multiply fourfold. "A method by which the fatty constituents suspended In milk may be quadrupled ."-London Daily Telegraph.