Rare, somewhat literary noun for a group of people, often with a nuance of 'fellows' or 'set'. Not used in everyday conversation; more likely encountered in older texts or formal writing.
He set out on a journey with his companions.
The kanji 徒 means 'follower' or 'companion', and 輩 means 'comrade' or 'fellow'. The compound is a straightforward combination of these elements, but the exact historical derivation is uncertain.