sunscreen vs sunblock

sunscreen and sunblock both are nouns.

Word	Noun	Adjective	Verb	Adverb
sunscreen	Yes	No	No	No
sunblock	Yes	No	No	No

As nouns, sunscreen and sunblock are synonyms defined as:

sunscreen and sunblock: a cream spread on the skin; contains a chemical (as PABA) to filter out ultraviolet light and so protect from sunburn

Other synonyms of sunscreen include sun blocker.

sunscreen (noun)	sunblock (noun)
a cream spread on the skin; contains a chemical (as PABA) to filter out ultraviolet light and so protect from sunburn	a cream spread on the skin; contains a chemical (as PABA) to filter out ultraviolet light and so protect from sunburn