Definition of observance

• n. - 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.
• n. - 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.
• n. - Servile attention; sycophancy.