How do you say sable in welsh?

There isn't a direct translation for "sable" in Welsh. This is because "sable" has several meanings:

* A dark brown fur: This is the most common meaning, but Welsh doesn't have a specific word for it. You would use a descriptive phrase like "ffwr brown tywyll" (dark brown fur).

* A type of weasel: Welsh has a word for this, "gelyn" (weasel), but this doesn't specify the sable weasel.

* A heraldic tincture: In heraldry, "sable" refers to black. The Welsh word for black is "du."

So, depending on the context, you would need to choose the appropriate Welsh phrase or word.