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Pap
PAP [isbe]
PAP - (shadh, shodh, "breast" (Ezek 23:21); mastos, "the breast" (Lk 11:27; 23:29; Rev 1:13)): The English word, which goes back to Middle English "pappe" (see Skeat, Concise Etymological Dictionary of the English Language, 327) and is now obsolete, has been replaced in the Revised Version (British and American) by "breast." The Hebrew word signifies the "female breast"; the Greek word has a wider signification, including the male chest.
Also see definition of "Pap" in Word Study