Pair
A pair was two individuals, animals, or things used as a group.

In the Talosian menagerie, for them to have descendants of specimens gathered from planets in the vicinity of Talos IV, it was required that they start with a pair, male and female, of each specimen. The Talosians had hoped to add a Human pair to their collection in 2254; however, this attempt failed as Humans were not suitable for captivity. ()

In 3189, Acting Captain Saru ordered that crewmembers work in pairs as they repaired the  until internal communications were reestablished. ()
Measurements