As stated up there in my comment, Heatran is an ideal counter to Clefable. Standard Clefable sets have nothing to hit it. All you really need to do is keep it relatively healthy and you can stop Clefable easily. I suggest Heatran over other Steel types, and there is two reasons for this. The first is its Fire immunity, as most good Clefable sets run Flamethrower.
Definition. The genitive is the case (or function) of an inflected form of a noun or pronoun showing ownership, measurement, association, or source. Adjective: genitival. The suffix -'s on nouns is a marker of genitive case in English.
In Latin it is used to indicate any number of relationships that are most frequently and easily translated into English by the preposition of: love of god, the driver of the bus, the state of the union, the son of god. The genitive case in Latin is also used adverbially with certain verbs.