Observance

Webster's Dictionary of the English Language

·noun Servile attention; sycophancy.

II. Observance ·noun An act, ceremony, or rite, as of worship or respect; especially, a customary act or service of attention; a form; a practice; a rite; a custom.

III. Observance ·noun The act or practice of observing or noticing with attention; a heeding or keeping with care; performance;

— usually with a sense of strictness and fidelity; as, the observance of the Sabbath is general; the strict observance of duties.