Synonyms for observed

Discover

discovered, seen, noticed, perceived, examined, considered, detected, discerned, looked, contemplated, witnessed, twigged, surveyed, espied, descried

Take notice

noted, mention'd, marked, attended, heeded, commented

Follow

watched, followed, eyed

Respect

respected, honor'd, obeyed

Other

celebrated, regarded, maintained, commemorated, fulfilled, discharged, solemnized