tricenarian

noun2

1. •
   A person in their thirties, a person aged between 30 and 39 years (inclusive).
2. •
   The highest rank and pay grade for prefectures in Ancient Rome.

   • In the honorific inscription CIL to his son-in-law he is described as vir perfectissimae memoriae, and thus must have risen to tricenarian rank. — 2008