unwritten law

An accepted although informal rule of behavior, as in It's an unwritten law that you lock the gate when you leave the swimming pool. [Mid-1400s]

Name	Pronounced	Usage
Arrow	['ærəu]
Pippin (2)	PIP-in (English)	Literature
Cindy	SIN-dee	English
Iskra	-	Bulgarian, Macedonian, Croatian, Serbian
Ognjan	-	Croatian, Serbian
Salvador	sahl-bah-DHOR	Spanish