D defs.my
Entry 1 sense Webster, 1913

Ultimo

· Ul·ti·mo · IPA /ˈʌltɪməʊ/
01 In the month immediately preceding the present; as, on the 1st ultimo; -- usually abbreviated to ult. Cf. Proximo.
  1. 1.
    In the month immediately preceding the present; as, on the 1st ultimo; -- usually abbreviated to ult. Cf. Proximo. See: Proximo