The affix khac comes after the verb tāp 'to heat' when dviṣat or para is the word in composition with it as an object.,
The verb तप् belongs both to Bhu and Chur classes. Both are meant in the sutra. In the case of Bhvadi, the verb तापि is the causative ending in णि of तप्; while in Churadi, all verbs take णि.
Thus द्विषन्तं तापयति = द्विषन्तपः 6.4.94 'one who destroys his enemies', so also परन्तपः 'one who subdues his enemies, a hero'.
This affix however, will not apply when the above upapadas are in the feminine gender. In this case the general affix अण् will be employed; as द्विषतीं तापयति = दिषतीतापः ।,