Lewis & Short

Ălētrĭum, i, n., a town in Latium, now Alatri; whence,

      1. a. Ălētrīnas, ātis, adj., pertaining to Aletrium, Cic. Clu. 16. —Ălētrīnātes, the inhabitants of Aletrium, Cic. Clu. 20; Plin. 3, 5, 9, § 63.
      2. b. Also, Ălētrīnensis, e, the same: foederatus, Cic. Balb. 22 dub.