Observance (Noun)

The act of observing; taking a patient look.

Nouns denoting acts or actions.

The astronomer's careful observance of the celestial bodies led to a groundbreaking discovery.
Her observance of the children's behavior helped her to identify the root cause of the problem.
The scientists' extended observance of the rare species provided valuable insights into its habits and habitats.
The detective's keen observance of the suspect's body language revealed a telling inconsistency in their alibi.
The artist's observance of the play of light on the landscape inspired a breathtaking series of paintings.