quadrupling n 1: increase by a factor of four
Quadruple \Quad"ru*ple\, v. t. [imp. & p. p. {Quadrupled}; p. pr. & vb. n. {Quadrupling}.] [L. quadruplare: cf. F. quadrupler.] To multiply by four; to increase fourfold; to double; to double twice. --A. Smith. [1913 Webster]