"duplicated, found in pairs," 1590s, from Latin geminatus "twinned, equal," past participle of geminare "to double, repeat," related to geminus "twin," perhaps from PIE *yem- "to pair." As a verb, from 1630s. Related: Geminated; geminating.
geminate gem·i·nate (jěm'ə-nĭt, -nāt')
Occurring in pairs.