Lewis & Short

1. ūnĭo, ĭi, ītum, 4, v. a. [unus], to join together, unite (post-Aug. and very rare; cf. conjungo): caelum mari, Tert. Anim. 17, Sulp. Sev. Chron. 2, 43, 1: corpora, Sen. Q. N. 2, 2, 4; Dig. 39, 2, 15, § 13; App. Mag. p. 283, 30.