The paper addresses the frequent collocation /ir(hu)waliyan parittarwaliyan/, which occurs in Luwian incantations embedded in Hittite cuneiform ritual texts. Despite the relatively clear context, the meanings of this and similar collocations have remained obscure. Using combinatory and etymological methods, we intend to demonstrate that it hides the merism “internal (or) external”, which modifies various sorts of supernatural negative phenomena. Furthermore, we intend to argue that such an interpretation is compatible with the Late Bronze Age Anatolian beliefs about potential sources of evil. A collateral result of our demonstration is the elucidation of a number of additional contexts in the Hittite, Luwian, Lydian, and official Aramaic languages.