What does surveilling mean?
Surveilling means watching or monitoring a person, place, or activity closely, usually for a security, law-enforcement, or investigative purpose. It may involve direct observation by people or continual recording by cameras and other devices. The word is commonly used in its present-participle form, both in sentences as the verb and before a noun, as in “surveilling camera.” Unlike the more neutral word “watching,” surveilling often suggests deliberate, systematic observation, with the attendant connotation of scrutiny, suspicion, or intrusion. In legal and workplace contexts, it can specifically refer to covert monitoring of someone's movements, communications, or activities. Its related noun, “surveillance,” is often used for the broader practice or system of observation. The precise legality and customary use of surveillance vary by jurisdiction and context.
To watch, observe, or monitor someone or something closely and continuously.
"Detectives surveilled the suspect's movements for several days."
This is the present participle of “surveil”; it is especially common in formal and legal contexts.
Engaged in the act of watching or monitoring someone or something.
"The surveilling officer followed the vehicle through the city."
Used attributively before a noun, especially to describe a person, device, team, or operation engaged in surveillance.
Its ancestry means “to watch over”: the word ultimately combines the Latin prefix for “over” with vigilare, “to keep watch.”
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does surveilling come from?
English borrowed the word through French surveiller, from Medieval Latin surveillare. That form combined the Latin prefix sur-, meaning “over,” with vigilare, “to keep watch,” and developed the sense of observing closely. The same Latin root is reflected in English words such as vigilance, vigilant, and vigil.
Related word forms
How surveilling is actually used
The form is most often used as the present participle of “surveil” and has a formal or technical tone. It often implies sustained or systematic observation, particularly by authorities, investigators, or surveillance systems.
Easily confused with surveilling
Surveilling means continuously watching or monitoring someone or something, whereas surveying generally means measuring land or examining a subject in detail.