An authoritative shari’a textual source (nass) whose authenticity is disputed by Muslim scholars. For example, for rulings based on qiyas, if there exists a weakness in the ‘illah (ratio legis) both for the asl (root) and the fare’ (branch), the hukm will be zanni or indefinite.

Nass zanni is an Arabic term (نص ظني) that translates as conjectural or probabilistic textual source.

The opposite of nass zanni is nass qat’ii.