minder vs keeper

minder and keeper both are nouns.

Word	Noun	Adjective	Verb	Adverb
minder	Yes	No	No	No
keeper	Yes	No	No	No

As nouns, keeper is a hypernym of minder; that is, keeper is a word with a broader meaning than minder:

minder: a person who looks after babies (usually in the person's own home) while the babys' parents are working
keeper: someone in charge of other people

minder (noun)	keeper (noun)
a person who looks after babies (usually in the person's own home) while the babys' parents are working	one having charge of buildings or grounds or animals
someone (usually in totalitarian countries) who is assigned to watch over foreign visitors	someone in charge of other people