(n.) A person sent secretly into an enemy's camp, territory, or fortifications, to inspect his works, ascertain his strength, movements, or designs, and to communicate such intelligence to the proper officer.

(2):

(n.) One who keeps a constant watch of the conduct of others.

(3):

(v. i.) To search narrowly; to scrutinize.

(4):

(v. t.) To explore; to view; inspect; and examine secretly, as a country; - usually with out.

(5):

(v. t.) To discover by close search or examination.

(6):

(v. t.) To gain sight of; to discover at a distance, or in a state of concealment; to espy; to see.

Bibliography Information
Webster, Noah. Entry for 'Spy'. Noah Webster's American Dictionary. https://www.studylight.org/dictionaries/eng/web/s/spy.html. 1828.

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