gatekeeper

UK: /ˈgeɪtkiːpə^r/ US: (gāt′kē′pər)

WordReference Random House Unabridged Dictionary of American English © 2025

gate•keep•er  (gāt′kē′pər), n. 

1. a person in charge of a gate, usually to identify, count, supervise, etc., the traffic or flow through it.
2. guardian;
   monitor:
   the gatekeepers of Western culture.

• gate¹ + keeper 1565–75

Collins Concise English Dictionary © HarperCollins Publishers::

gatekeeper / ˈɡeɪtˌkiːpə/ noun

1. a person who has charge of a gate and controls who may pass through it
2. any of several Eurasian butterflies of the genus Pyronia, esp P. tithonus, having brown-bordered orange wings with a black-and-white eyespot on each forewing: family Satyridae
3. a manager in a large organization who controls the flow of information, esp to parent and subsidiary companies