foreign matter
Substance not belonging
Foreign matter is any substance that doesn't belong in a particular place or context.
The term appears most often in quality control, medicine, and food safety: The X-ray revealed foreign matter in her lung.
A speck of dust in a wound, metal shavings in machinery, or an insect in packaged food all qualify as foreign matter—unwanted material that has intruded where it shouldn't be.
- debrisScattered broken fragments
- contaminationIntroduction of impurities
- impuritySubstance degrading another's quality
- particleMinute piece of matter
- dust particleMinute airborne solid fragment
speck · dust · splinter · splinter removal · grit · residue · intrusion · pollutant · sediment · fragment · alien · obstruction · infiltration · unwanted · irritant · invasion · lodged · embedded
- food hazardspathogens, toxins, parasites, viruses, bacteria
- grain qualityprotein content, moisture content, gluten content, hardness, dockage
- defectsdefect, flaw, crack, cracks, defective
- wastetrash, garbage, rubbish, refuse, debris
- adulterantsmelamine, borax, chalk, sawdust, filler
- collector errorsdouble strike, off-center, misprint, cud, mule