"Just say no" sayer

• Teetotaler
• Addict's antithesis
• Clean type
• Abstaining individual
• Clean fellow
• One avoiding consumption that could make nose run
• Abstainer

Wiktionary Word definitions in Wiktionary
n. 1 A person who is not a user (of drugs, a computer system, etc.). 2 Lack of usage; failure to use. 3 (context legal English) Neglect or omission to use an easement or franchise or to assert a right.

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Nonuser \Non*us"er\, A not using; failure to use. An office may be forfeited by misuser or nonuser. --Blackstone. (Law) Neglect or omission to use an easement or franchise or to assert a right. --Kent.