Also found in: Dictionary, Thesaurus, Wikipedia.
A chemical preparation, such as zinc oxide, that is applied to the skin to protect it from the ultraviolet rays of the sun.
sunblockPublic health An opaque substance, usually formulated from zinc or titanium oxides, designed to completely prevent solar radiation from reaching the skin. See SPF rating. Cf Sunscreen.
Patient discussion about sunblock
Q. what does a sun block cream do? and what are a UV rays?
A. It blocks out harmful Ultra violet rays from the skin as the previous entries have related; however it can also block your ability to produce vitamin D. If you live in a northerly area or one that receives limited sunlight, its recommended to get at least 15 minutes of sun a day (this is probably best done with minimal sunblock) and according to personnal sun sensitivity. Another thing to keep in mind is that sunblock works best if applied 20 minutes before sun exposure.More discussions about sunblock