residue
UK: ˈrɛzɪdjuː | US: ˈrɛzɪduː
n. a small amount of something that remains after the main part has gone or been taken or used
n. (chemistry) a substance remaining after a process such as combustion or evaporation
The word "residue" traces back to Latin residuum, meaning "what is left behind." It combines re- (indicating reversal or remaining) with sedere (to sit), metaphorically describing matter that "sits" or settles after a process. The term entered Middle English via Old French residu, retaining its core idea of remnants.
After filtering the solution, a dark residue was left in the beaker.
The residue of ancient civilizations can still be found in these ruins.
Wash the pan thoroughly to remove any food residue.
The fire left only a charred residue of the documents.
Chemical analysis detected trace residues of pesticides in the soil.