observed
v.v. to watch something carefully to learn more about it, or to follow a rule or custom. You use this when you pay close attention to details or respect a tradition.
v. to watch or monitor something attentively for scientific or analytical purposes; to comply with a law, custom, or regulation. Transitive in both its empirical and legal senses.
The scientists observed the birds for several weeks.
The security team observed the crowd's behavior through the cameras to ensure everyone followed the safety rules.
While the researchers observed a significant shift in the data over the fiscal quarter, the local community strictly observed traditional customs that had remained unchanged for centuries.
The verb is transitive and requires a direct object. When used to mean 'follow a rule', it is more formal than 'follow' or 'obey'.