observation

The word can be used as both a countable and uncountable noun depending on the meaning. When referring to a specific remark or comment, it is usually countable (e.g., "one observation"). When talking about the process of monitoring something, it is often uncountable (e.g., "under observation"). In the context of following rules or laws, it is a formal term and is less common in casual conversation than words like "following" or "obeying".