What is the denotation of sunscreen?

Something you apply when you go outside to avoid sunburn.

Explanation:

Denotation is the literal meaning of something, as opposed to connotation, which is the implied meaning, as in "eccentric" implies something negative, and "whimsical" implies something positive. Sunscreen is what it is.

a cream or lotion rubbed on to the skin to protect it from the sun.