noun · a ruffian, hooligan, or person with no legitimate profession who lives by their wits or antisocial means

他整天和一群社会混子聚在一起，不干正事。

noun · a person who drifts through life or work without effort, goals, or contribution; one who just muddles through

他在办公室里就是个混子，从来不主动承担任务。