sitter vs baby-sitter

sitter and baby-sitter both are nouns.

Word	Noun	Adjective	Verb	Adverb
sitter	Yes	No	No	No
baby-sitter	Yes	No	No	No

As nouns, sitter and baby-sitter are synonyms defined as:

sitter and baby-sitter: a person engaged to care for children when the parents are not home

Other synonyms of sitter include babysitter.

sitter (noun)	baby-sitter (noun)
a domestic hen ready to brood	a person engaged to care for children when the parents are not home
a person engaged to care for children when the parents are not home
an organism (person or animal) that sits
a person who poses for a painter or sculptor