The original side of jurisdiction is when you file a case directly in that particular case, instead of filing an appeal from judgement of some other lower court. e.g. a writ petition in the high court invoking its jurisdiction under Article 226 of the Constitution of India is filed on its "original side". Similarly, an Election Petition challenging election of MLA / MP, is filed in the high court on its original side.

i agree with Adv Goel