Legal (adjective)

1. Relating to the law, or to the profession of law.
2. Conforming to the law, or to the rules and regulations of a particular profession or activity.
3. Permissible or recognized by law.

Origin:

Late middle english: from old french, or from latin legalis, from lex, leg- "law".

Examples:

1. He is a legal representative.
2. She is a legal secretary.
3. The legal drinking age is 21.
4. It is legal to vote at 18.
5. The legal limit for blood alcohol content is .08.