sliding board vs playground slide

sliding board and playground slide both are nouns.

Word	Noun	Adjective	Verb	Adverb
sliding board	Yes	No	No	No
playground slide	Yes	No	No	No

As nouns, sliding board and playground slide are synonyms defined as:

sliding board and playground slide: plaything consisting of a sloping chute down which children can slide

Other synonyms of sliding board include slide.

sliding board (noun)	playground slide (noun)
plaything consisting of a sloping chute down which children can slide	plaything consisting of a sloping chute down which children can slide