sunscreen vs sun blocker

sunscreen and sun blocker both are nouns.

Word	Noun	Adjective	Verb	Adverb
sunscreen	Yes	No	No	No
sun blocker	Yes	No	No	No

As nouns, sunscreen and sun blocker are synonyms defined as:

sunscreen and sun blocker: 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 sunblock.

sunscreen (noun)	sun blocker (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