or sun block
a substance that provides a high degree of protection against sunburn, often preventing most tanning as well as burning, as by obstructing the penetration of ultraviolet rays.
a lotion, cream, etc., containing such a substance.
Origin of sunblock
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
A preparation, as of PABA, that prevents sunburn by filtering out the sun's ultraviolet rays, usually offering more protection than a sunscreen.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.