The name Janus originates from the Latin word 'ianua', meaning 'archway' or 'doorway'. In ancient Roman religion and myth, Janus is the god of beginnings, gates, transitions, time, duality, doorways, passages, frames, and endings. He is often depicted with two faces, symbolizing his ability to look into the past and future simultaneously. The month of January is named after Janus, reflecting his association with new beginnings and transitions.