Keeper
Part of speech: noun
Definition: A person who keeps something. Someone or something worth keeping. A person charged with guarding or caring for, storing, or maintaining something; a custodian, a guard. The player charged with guarding a goal or wicket. Short form of goalkeeper, wicketkeeper. A part of a mechanism that catches or retains another part, for example the part of a door lock that fits in the frame and receives the bolt. An offensive play in which the quarterback runs toward the goal with the ball after it is snapped.
Example sentence: As a keeper, you have to understand that your job is black and white: you make a save, or you don't; you can be the hero - or the goat.
Custodian
Part of speech: noun
Definition: A person entrusted with the custody or care of something or someone; a caretaker or keeper.(US) a janitor (US); a cleaner
Example sentence: The constitution is the ultimate custodian of social will and its making should be accorded all due diligence.