> a habit is something you do habitually That soounds a tiny bit circular. Doesn't "habitually" mean to do something out of habit? I'd suggest "habit" is some

> a habit is something you do habitually That soounds a tiny bit circular. Doesn't "habitually" mean to do something out of habit? I'd suggest "habit" is something we often do, but don't really need to do, If it's something we have to do, like eating we don't call it a habit.