Lewis & Short

Lārentĭa (Lārentīna, Lact. 1, 20 init.), ae, f. (also called Acca Larentia), acc. to the myth, the wife of Faustulus, and mother of the twelve Arval Brothers, who suckled and reared the twins Romulus and Remus, Ov. F. 3, 55; Liv. 1, 4, 7; Gell. 6, 7; Varr. L. L. 6, § 23 Müll.
Lārentā-lia, ium, n., the festival celebrated in honor of Larentia, on the 23d of December, Ov. F. 3, 57; Paul. ex Fest. p. 119 Müll.
Also in a lengthened form: ‡Lārentīnal, Varr. L. L. 6, 3, 58, § 23 Müll.