noun - a person who enjoys not wearing clothes, especially at the beach or in nature, often as part of a lifestyle or belief in natural living
noun, technical - a serious mental condition in which a person gradually loses the ability to think, remember, and behave normally, usually because of disease or old age
noun - a narrow channel or small valley formed by running water, especially after heavy rain; a channel or passage for carrying water away, especially at the side of a road or roof