means A formal ceremony or set of actions performed in a prescribed way, often marking a religious or social transition.

from From Latin 'ritus,' meaning a religious observance or custom — the established way a thing is properly done. It came into English through Old French, and it's likely a distant cousin of words tied to counting and ordering (possibly related to the same root that gives us 'arithmetic'), as if a rite were the world's oldest fixed sequence: do this, then this, then this, and the change takes hold.