Residue/ˈrezɪduː/ Definition 1 of 6Pro Tip 1/3Physical Presence Refers to actual material left behind, often visible and sometimes unwanted. Cleaning the pan, I scrubbed off the oily residue. Pro Tip 2/3Not Always Negative While often undesirable, residue can also be valuable or neutral. The residue in the bottom of my coffee cup had a robust aroma. Pro Tip 3/3Context Matters Its meaning can change slightly depending on what it's referring to. The geologists examined the mineral residue at the site.