Yes, it is. It usually refers to a person who is in charge of some important thing, as in 'Keeper of Records' for an agency, or 'keeper of the flame'. Commonly it might be used as 'he's [or she's] a keeper', meaning a person who is worth knowing and developing a relationship with. If the latter use is not yet accepted as standard, it will be eventually.
Drug and keeper
housekeeper
Doorman.
House keeper
A Cheeseclacker
zookeeper
Knowledge keeper.
zookeeper
Banker
Tender
The word means jail keeper or warden.
shepherd