stroller vs walker

stroller and walker both are nouns.

Word	Noun	Adjective	Verb	Adverb
stroller	Yes	No	No	No
walker	Yes	No	No	No

As nouns, walker is a hypernym of stroller; that is, walker is a word with a broader meaning than stroller:

Other hypernyms of stroller include footer, pedestrian.

stroller (noun)	walker (noun)
a small vehicle with four wheels in which a baby or child is pushed around	an enclosing framework on casters or wheels; helps babies learn to walk
someone who walks at a leisurely pace	a light enclosing framework (trade name Zimmer) with rubber castors or wheels and handles; helps invalids or the handicapped or the aged to walk
	a shoe designed for comfortable walking
	a person who travels by foot