"Fingertip tight" is a term used in canning to describe the proper level of tightness when applying the canning jar lids and rings. It means that you should tighten the rings until they are comfortably snug using just your fingertips, without applying excessive force. The goal is to create a seal that is secure enough to prevent leaks during processing but not overly tight, allowing air to escape and creating a vacuum seal once the jars cool. It's important not to overtighten the lids, as it can interfere with the sealing process.