observation

noun

• 1 [mass noun] the action or process of closely observing or monitoring something or someone:she was brought into hospital for observation units kept enemy forces under observation for days [count noun]:detailed observations were carried out on the students' behaviour
• the ability to notice things, especially significant details:his powers of observation
• the act of taking the altitude of the sun or another celestial body to find a latitude or longitude.

• 2a statement based on something one has seen, heard, or noticed:he made a telling observation about Hughie