A / assectātĭo
noun

assectātĭo

gen. assectātōnis · gender feminine · decl. 3rd
(), , assector.
respectful; attendance
An (assiduous, respectful) attendance (as that of clients, etc.): in petitionibus opera atque adsectatio, Cic. Mur. 34: so Q. Cic. Petit. Cons. 9.—
Observation; study
Observation, study: magna caeli adsectatio, Plin. 2, 20, 18, § 82.