Skip to Content
Medical Term:


Pronunciation: sŭb-stan-tiv′i-tē

Definition: Term comprising the adherent qualities of a sunscreen and its ability to be retained after the skin is exposed to water and perspiration. Persistence of effect of a topically applied drug or cosmetic, determined by the degree of physical and chemical bonding to the surface; resistance to removal or inactivation by sweating, swimming, bathing, and friction, among other factors.