shingle vs crushed rock

shingle and crushed rock both are nouns.

Word	Noun	Adjective	Verb	Adverb
shingle	Yes	No	Yes	No
crushed rock	Yes	No	No	No

As nouns, crushed rock is a hypernym of shingle; that is, crushed rock is a word with a broader meaning than shingle:

shingle: coarse beach gravel of small waterworn stones and pebbles (or a stretch of shore covered with such gravel)
crushed rock: rock fragments and pebbles

Other hypernyms of shingle include gravel.

shingle (noun)	crushed rock (noun)
a small signboard outside the office of a lawyer or doctor, e.g.	rock fragments and pebbles
building material used as siding or roofing
coarse beach gravel of small waterworn stones and pebbles (or a stretch of shore covered with such gravel)

shingle (verb)	crushed rock (verb)
cover with shingles