1
general::
Keep an area or person under police surveillance; also, assign someone to conduct such a surveillance. For example, They staked out the house, or He was staked out in the alley, watching for drug dealers. [c. 1940]
American Heritage Idioms
2
general::
Phrase(s): stake someone or something out
1. to position a person so that someone or something can be observed or followed. • The cops staked the car out and made the arrest. • Barlowe staked out the apartment building and watched patiently for an hour. 2. to position a person to observe someone or something. • He staked his best operative out in front of the building. • We staked out two men to keep watch.
McGrawhill's American Idioms And Phrasal Verbs