Compositional etymology. Since μῆλον can refer to sheep or to goats, the motivation of the etymology is taken from the behavior of young animals, especially the kids. The etymology is backed by a semantic parallel deriving αἴξ "goat" from ἀΐσσω "to leap". Therefore, we are dealing here with a false syllogism, in which « A. the goat is a μῆλον, B. the goat is the "jumping" animal, therefore C. the μῆλον is a jumping animal », which can be obtained if the initial /I/ of ἴφιος is thought to be the verb εἶμι. Then the /ph/ is related to the adverb σφόδρα, which is assumed to be equivalent to λίαν "much, too much", often used in compositional etymologies as a gloss of "intensive" ἀ-. Needless to say, heavy formal manipulations are required between the etymon and the lemma, when only one consonant is left from the etymon σφόδρα (modernized in σφορδῶς in Apollonius' wording)