Eighth
Tavius is a modern shortened form of Octavius, a Roman family name. In Latin, it specifically denotes the eighth child or someone born in the eighth month. While rare today, it retains the rhythmic, classical weight of its Roman origins in a more accessible, two-syllable format.
Less common today
Tavius isn't in the latest US Top 1000. It last peaked at #4,074 in 1999.
NFL outside linebacker
US births per 5-year period, 1990βpresent (SSA data).