liver spot

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A benign, localized brownish patch on the skin, often occurring in old age and usually in fair-skinned people with sun-damaged skin. Also called age spot.

Wiktionary

1. n. A dark brown blemish on the skin, usually caused by exposure to the sun.

WordNet 3.0

1. n. a type of skin disease that causes brown spots on the skin