noun (n)

• the act of observing; taking a patient look(noun.act)

  Synonym:
  observation, watching
  

  source: wordnet30
• a formal event performed on a special occasion(noun.event)

  Synonym:
  ceremonial, ceremonial occasion, ceremony
  

  source: wordnet30
• the act of noticing or paying attention(noun.cognition)

  Synonym:
  notice, observation
  

  source: wordnet30
• conformity with law or custom or practice etc.(noun.act)

  Synonym:
  honoring
  Antonym:
  nonobservance
  

  source: wordnet30
• 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.(noun)

  source: webster1913