إن

إِنْ \ if: (in regard to sth. certain) when: Ice melts (or will melt) if you heat it, (usu. not followed by the future tense) on condition that; provided that: If you go, I shall go too. \ إِنْ سارَت الأمورُ إلى الأسوأ \ if the worst comes to the worst: if things become as bad as possible.