Answer: unwritten

AnswerCrossword Clue
UNWRITTENNot on the books, as a law
UNWRITTENCustomary, as some rules
UNWRITTENTraditional but not official.
UNWRITTENKind of law
UNWRITTENTacit
UNWRITTENType of law?
UNWRITTENOral only
unwrittenNot recorded in writing
unwritten(of a convention) Understood and accepted by everyone, although not formally established
unwritten(esp. of a law) Resting originally on custom or judicial decision rather than on statute