pulley block vs pulley

pulley block and pulley both are nouns.

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

As nouns, pulley block and pulley are synonyms defined as:

pulley block and pulley: a simple machine consisting of a wheel with a groove in which a rope can run to change the direction or point of application of a force applied to the rope

Other synonyms of pulley block include block, pulley-block.

pulley block (noun)	pulley (noun)
a simple machine consisting of a wheel with a groove in which a rope can run to change the direction or point of application of a force applied to the rope	a simple machine consisting of a wheel with a groove in which a rope can run to change the direction or point of application of a force applied to the rope