sun blocker vs sunscreen

sun blocker and sunscreen both are nouns.

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

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

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

Other synonyms of sun blocker include sunblock.

sun blocker (noun)	sunscreen (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