From Latin 'habitus' (condition, dress), from 'habēre' (to hold) — clothing and behavior are both things held onto.
A settled tendency or behavior; a garment worn by a religious order.
From Old French 'habit,' from Latin 'habitus' (condition, dress), from 'habēre' (to have, hold). A habit is something you 'hold' — both a garment and a behavior. Key roots: habēre (Latin: "to have, hold").