The name Octavius is boy's name of Latin origin meaning "eighth".

Octavius, which was at one time used for the eighth child in a family, has the worn leather patina of all the ancient Roman names now up for reconsideration. As a Roman family name, it derives from the uncommon forename Octavus, which designated an eighth son.

The first Roman emperor, Augustus, was called Caius Octavius or Octavian before he took his title. He was the son of Octavius and Atia, the niece of Julius Caesar, who adopted him as his son. He appears under the name Octavius Caesar in Shakespeare's "Julius Caesar" and "Antony and Cleopatra."

In later lit, Octavius Guy is a character in Wilkie Collins's novel The Moonstone and Octavius Robinson is in George Bernard Shaw's play "Man and Superman," while Octave is the name of the protaganist of a Stendhal novel. And Octavius is the name of an old Roman general in the movie "Night at the Museum."

Attractive foreign versions include Ottavio and Octavio, as in the distinguished Mexican poet Octavio Paz. Octavio is also the name of several saints, including one who lived as a hermit in an elm tree.