Sunburn is a condition caused by overexposure to the sun's ultraviolet rays, resulting in REDNESS and pain of the skin. The two crossword solutions for the term SUNBURN are REDNESS (7 letters) and TAN (3 letters). REDNESS is a common symptom of sunburn, as the skin becomes inflamed and irritated due to the UV radiation. Tanning is the opposite of sunburn, as it is the result of exposure to the sun's UV rays, resulting in a darker color of the skin.