μετατῠπ-ωσις · metatyp-ōsis — LSJ
transformation, Ammon. Diff. p.91 V.
conversion of a compound word into two simple ones, as ἀκρόπολις into ἄκρα πόλις, Eust. 626.49, cf. 75.4.
defined as λέξις ἐνηλλαγμένα στοιχεῖα ἔχουσα (as ὑπαί for ὑπό), Trypho Trop. 2.16.