cylinder block vs cylinder

cylinder block and cylinder both are nouns.

Word	Noun	Adjective	Verb	Adverb
cylinder block	Yes	No	No	No
cylinder	Yes	No	No	No

cylinder block (noun)	cylinder (noun)
a metal casting containing the cylinders and cooling ducts of an engine	a cylindrical container for oxygen or compressed air
	a chamber within which piston moves
	a surface generated by rotating a parallel line around a fixed line
	a solid bounded by a cylindrical surface and two parallel planes (the bases)