Lewis & Short

Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.

Caeso (Kaeso, v. the letter K), ōnis, m. [a caeso matris utero dictus, Plin. 7, 9, 7, § 47; cf. Paul. ex Fest. p. 57 Müll.; Isid. Orig. 9, 3, 12, and v. Caesar init.], a Roman cognomen in the gens Fabia, Liv. 2, 43, 2; 2, 48, 3 and 4; 3, 11, 6 sq. et saep.

Caesōnĭus, a, name of a Roman gens.
So,

  1. I. M. Caesonius, œdile with Cicero, Cic. Att. 1, 1, 1; 1, 12, 11; id. Verr. 1, 10, 29.
  2. II. Caesonius Paetus, consul under Nero, Tac. A. 14, 29.
    Hence, Caesōnĭānus, a, um, adj., Col. 1, 4, 1.
  3. III. Milonia Caesonia, mistress and afterwards wife of Caligula, Suet. Calig. 25; Juv. 6, 616.