Decuple \Dec"u*ple\, n. A number ten times repeated. [R.] Decuple \Dec"u*ple\, v. t. [imp. & p. p. {Decupled}; p. pr. & vb. n. {Decupling}.] To make tenfold; to multiply by ten. [R.] Decuple \Dec"u*ple\, a. [F. d['e]cuple, L. decuplus, fr. decem ten.] Tenfold. [R.]