Meaning of unwritten

Definition of unwritten

(adj) based on custom rather than documentation; "an unwritten law"; "rites...so ancient that they well might have had their unwritten origins in Aurignacian times"- J.L.T.C.Spence
using speech rather than writing; "an oral tradition"; "an oral agreement"
said or done without having been planned or written in advance; "he made a few ad-lib remarks"

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