benzophenone
Noun
Meaning
(organic chemistry, countable) Any of a class of aromatic ketones based on the parent compound diphenylketone (C6H5)2CO; used, amongst other things, as ingredients in sunblock.
(organic chemistry, uncountable) The compound diphenylmethanone.
Source: en.wiktionary.orgExamples
Benzophenone is a contaminant in the sunscreen octocrylene.