0 a person whose job is to open and close a gate and to prevent people entering without permission --
The professors act as gatekeepers who determine which students are admitted into the competetive engineering program.
1 a person or organization that controls whether people can have or use a particular service: --
We can complete it step by step however long the road is and it can't be completed however short the road is if you don't even mark your footprint.
Vi kan slutföra det steg för steg hur lång vägen än är och den kan inte slutföras hur kort vägen än är om du inte ens markerar ditt fotavtryck.