1. the practice of following or keeping a custom, rule, ceremony, or religious law
2. a ceremony or ritual, especially a religious one

Examples

• The observance of religious holidays is important to many families.
• Strict observance of traffic laws helps prevent accidents.
• The memorial observance honored fallen soldiers.
• Their observance of traditional customs has been passed down for generations.
• The school requires observance of the dress code.
• The observance included prayers and special readings.
• Many people find comfort in the observance of daily rituals.