Glossary
Residue — Glossary
The material left behind on a surface — the physical source of the odor.
Residue is the deposit a pet leaves on a surface — urine, oils, dander, moisture. It’s the source of the smell: the odor you perceive is the compounds the residue is releasing.
Everything else — masking, fragrance — is downstream of this. Remove the residue and the odor stops at the source.