pulley vs pulley block

pulley and pulley block both are nouns.

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

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

pulley and pulley block: 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 include block, pulley-block.

pulley (noun)	pulley block (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