1650s, from Latin quadruplicatus, past participle of quadruplicare "make fourfold," from quadri- "four" (see quadri-) + plicare "to fold" (see ply (v.1)).[quadruplicate etymology, quadruplicate origin, 英语词源]
1660s, from Latin quadruplicatus, past participle of quadruplicare "make fourfold," from quadri- "four" (see quadri-) + plicare "to fold" (see ply (v.1)). Related: Quadruplicated; quadruplicating.