The definition of an adjective is a part of speech that is used to describe a noun. Red, tall, better and fast are all examples of adjectives.
In modern parlance, a gentleman (from gentle + man, translating the Old French gentilz hom) is any man of good, courteous conduct. A gentleman may also simply be a polite term for any man, as in indications of gender-separated facilities, or as a sign of the speaker's own courtesy when addressing others. The modern female equivalent is lady.
a man excessively concerned with his clothes, grooming, and manners. Slang. a fellow; chap. (a general term of address used to a man, woman, or group). a person reared in a large city. Western U.S. an urban Easterner who vacations on a ranch. (an expression of shock, approval, sympathy, or other strong feeling): Dude!