The name Jax is a boy's name . Jax is ranked #222 on our popularity charts and is often added to lists like Nicknames for Boys and discussed in our forums with posts like "What would be the perfect twin?".
From the experts:
Jax is the Dex-Jex-Pax type of x-ending cool -- possibly too cool -- variation of Jack or nickname for Jaxon or Jackson.
Jax was a soap opera character name way back when; most recently he's been seen as Jackson "Jax" Teller, the central character on Sons of Anarchy, the national president of the Sons of Anarchy Motorcycle Club.