From Middle English residue, from Old French residu, from Latin residuum, neuter of residuus (“remaining”), from resideō (“I remain behind”). residue (countable and uncountable, plural residues) Whatever remains after something else has been removed.

The noun residue can be countable or uncountable. In more general, commonly used, contexts, the plural form will also be residue. However, in more specific contexts, the plural form can also be residues e.g. in reference to various types of residues or a collection of residues. Find more words!