What’s the English word for the metallic “dust”, or more precisely the tiny remains (waste) of drilling, welding, cutting through metal, and similar metal processing?

  • Even inside the metalworking community swarf isn't used. -Source, an old foundry man; Dad.
    – Mazura
    Commented Dec 17, 2014 at 2:38
  • I don't think you'll find a single word that describes the metal waste from all common metalworking operations. Metalworking has an astonishingly rich tradition of specific and unambiguous vocabulary for almost every material and action you'll encounter.
    – alx9r
    Commented Dec 17, 2014 at 5:11
  • Deja Vu: I just had a conversation earlier today on whether the term "saw dust" could apply to substances other than wood. (We decided it could.) +1 for the question.
    – cobaltduck
    Commented Dec 17, 2014 at 20:34

9 Answers 9


I think you're looking for the word shavings.

Filings would be ok, too.

  • 4
    iron filings, yeah exactly. Commented Dec 16, 2014 at 19:17
  • The guy who says filing at the other end of the link in this answer, sounds really happy to be saying filing.
    – Daft
    Commented Dec 18, 2014 at 14:59

You could generally use Swarf, which also works for other materials too.

Swarf generally implies relatively big pieces of waste though, "metal dust" would be acceptable if you really do end up with a very fine powder.

Additionally, when grinding something, people tend to refer to the metal that goes flying as sparks

  • Great, thanks. There are even several phrases like "metal debris" mentioned in that Wiki page which will work neat. Yeah, it's not really fine powder, but I couldn't find the right word so I hoped someone would get it right.
    – vgru
    Commented Dec 16, 2014 at 10:14
  • In machine shops where I've worked swarf is only used to refer to the metal waste produced by machining operations like drilling, milling, or turning. Swarf is distinct from filings and grindings. At best, swarf refers to a small subset of what OP describes.
    – alx9r
    Commented Dec 17, 2014 at 5:03
  • I suspect (well, in New Zealand English, at least... which is where I am), "swarf" is not a commonly used term for these debris. I've never heard it used, but have certainly heard "filings" and "shavings".
    – inspirednz
    Commented Jun 1, 2019 at 4:40

In the jewellery trade it is known as lemel or lemels. An alteration of earlier limall, limmell, from Middle English lemaille, limail, from Middle French limaille, from Old French, from limer to file, from Latin limare. (Merriam-Webster Online)

Though in all the years of living with my father, a Silversmith, I never heard him use the word. He simply called it filings or scrap, depending on size. Though it was always assiduously collected.

  • I agree with your father's terminology. In my experience with CNC steel lathes, the tiny fragments of metal shaved off of the product are referred to as scrap (these pieces being as little as 1 cubic mm). When filing down something made of metal, a much finer dust is produced, so filings is also quite fitting for this question.
    – talrnu
    Commented Dec 16, 2014 at 15:31

The metalwork equivalent of sawdust is "swarf"

The OED has this as:

Fine chips or filings of stone, metal, or other material produced by a machining operation:


For the small pieces that come off from a machining process like drilling, milling, or turning on a lathe, these are often called turnings if you are selling them to a scrap hauler. The smallest "dust-sized" pieces that would come from grinding or saw-cutting are sometimes also known as filings or fines.

When I learned to program a CNC laser some years ago, I was taught to call the small waste metal pieces that indicated a less than perfect cut dross. This same waste from an plasma cutter or oxygen-acetylene torch would more usually be referred to as slag, although I always saw little difference between the two terms.


Well... any takers for 'Robocoke' ? Seriously, I'd have to go with 'metal dust' ... swarf seems to describe much about a gathering of coils and larger shavings left under a lathe. In a sentence, "Iron Man left his failed attempt among the metal dust and swarf."


In chemistry and chemical processing, a single-material powder or granulated material can be referred to as a 'sponge' due to the very high surface (reaction) area.


For residue produced from machining: I'd vote for "filings" if the residue is small and dust-like. For bigger bits of leftovers, as in those left over from lathe work, the term I've heard is "chips". (Trivia du jour: I used to work at a specialty steel maker who produced steels specifically designed to ensure good chip breakage - i.e. that didn't leave those long and potentially problematic "curls" of (sharp!) steel).

For welding or cutting residue: I've heard it referred to as "spatter".



Powder? That's what I'd go for.

  • It wasn't really fine powder I had in mind, but I didn't really know how to express it.
    – vgru
    Commented Dec 16, 2014 at 10:25
  • 7
    Welcome to English Language & Usage @Eamonn. Your post would be improved if it included a reference and an explanation of why it answers the question. See the help center to learn more about how to write a strong answer.
    – user63230
    Commented Dec 16, 2014 at 10:45

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.