An Etymological Dictionary of Astronomy and Astrophysics

Eightfold; eight times as great.

Etymology (EN): L. octuplus, from octu- variant (before labials) of → oct- octa- + -plus “fold,” from base of plicare “to fold, twist.”

Etymology (PE): Haštâyi, from hašt “eight,” → oct- octa- + -tâyi, from tâ “fold, plait, ply; piece, part,” also a multiplicative suffix; Mid.Pers. tâg “piece, part.”