Lewis & Short

Mytĭlēnē (in later times Mĭtylēnē), ēs, f., and Mytĭlēnae, ārum, f., = Μυτιλήνη, the capital of Lesbos, the birthplace of Sappho, Pittacus, Alcæus, and Diophanes, the orator, now Mytilini or Castro.
Mytilene: laudabunt alii claram Rhodon, aut Mytilenen, Hor. C. 1, 7, 1; id. Ep. 1, 11, 17 al.
In plur. form, Mytilenae: Mytilenis an Rhodi malles vivere, Cic. Agr. 2, 16, 40; id. Fam. 4, 7, 4; Suet. Caes. 2; id. Aug. 66; id. Tib. 10; Caes. B. C. 3, 102, 5.
Hence,

    1. 1. Mytĭlēnaeus (Mĭty-), a, um, adj., = Μιτυληναιος and Μυτιληναίος, of or belonging to Mytilene, Mytilenean: mango, Mart. 7, 80, 9: vulgus, Luc. 8, 109: Theophanes, Tac. A. 6, 18.
      As subst.: My-tĭlēnaei, ōrum, m. (sc. incolae), the inhabitants of Mytilene, the Mytileneans, Vell. 2, 18, 3.
    2. 2. Mytĭlēnensis, e, adj., of or belonging to Mytilene: secretum, Tac. A. 14, 53.