rītus

Consuetudo denotes the uniform observance of anything as a custom, arising from itself, and having its foundation in the inclination or convenience of an individual or people, ἔθος; whereas mos (modus) is the habitual observance of anything, as a product of reason, and of the self-conscious will, and has its foundation in moral views, or the clear dictates of right, virtue, and decorum, ἦθος; lastly, ritus denotes the hallowed observance of anything, either implanted by nature as an instinct, or introduced by the gods as a ceremony, or which, at any rate, cannot be traced to any human origin. Consuetudines are merely factitious, and have no moral worth; mores are morally sanctioned by silent consent, as jura and leges by formal decree; ritus (from ἀριθμός, ῥυθμός), are natural, and are hallowed by their primæval origin, and are peculiar to the animal. (v. 75.) 2. Ritus is a hallowed observance, as directed and taught by the gods or by nature; whereas cærimonia (κηδεμονία) is that which is employed in the worship of the gods.