noun:1)An individual who is old enough to take complete responsibility for all of his/her actions. Often described by the goverment as a person who has reached a certain age (e.g. a person 18 years old or more). Adjective: 2)Pertaining to adults. 3)Describing sexually suggestive material.
1) Only adults are allowed to buy tobacco here.
2) Little Mindy asked why some things were too adult for her to understand.
3) Strip clubs offer adult entertainment.