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.
Their most often use is non-finite verbs. In traditional descriptions of English, the infinitive is the basic dictionary form of a verb when used non-finitely, with or without the particle to. Thus to go is an infinitive, as is go in a sentence like I must go there (but not in I go there, where it is a finite verb).