One of the Utonality correlatives...; example: "the 5 Udentity of 7/4 unity is 7/5".
A simpler way to express Partch's definition is to say that an udentity is an identity of an utonality. In common music-theory terminology, an udentity is a member of a minor chord, but measured by 3rds downward from the 5th (rather than upward from the root as in a major chord).
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