gemin-

Existing or arranged in two pairs; specifically in medicine, applied to the corpora quadrigemina of the brain, lying beneath the cerebral hemispheres.

A constellation, otherwise 'Castor and Pollux'; also the third sign of the zodiac, with which this constellation was anciently identical.

Having flowers arranged in pairs.

Double; occurring in pairs.

Triple; pertaining to the fifth cranial nerve (nervus trigeminus); called the fifth pair of cranial nerves because of their division into three branches; also called 'trifacial'.

The condition of occurring in threes, especially the occurrence of three pulse beats in rapid succession.