The Collaborative International Dictionary
Septupling
Septuple \Sep"tu*ple\, v. t. [imp. & p. p. Septupled; p. pr. &
vb. n. Septupling.]
To multiply by seven; to make sevenfold.
--Sir J. Herschel.
Wiktionary
septupling
vb. (present participle of septuple English)