Caddo ethnic terms

[Koontz John E]

On Wed, 31 Jul 2002, Wallace Chafe wrote:
> Unlike John, I find it hard to let go of Mexicanos as the origin of ka:nos
> etc. It seems relevant that among the Tonkawas ka:nos did in fact mean
> Mexicans.

That information would change matters considerably.  I missed it earlier.
I thought the term was only attested as 'Frenchman'.

> So we have the Tonkawas with that meaning, and their neighbors,
> Caddos and others, with the meaning Frenchmen for what seems obviously to
> be the same word. Exactly how that happened, historically and
> sociopolitically, may be a puzzle, but clearly we need to know a lot more
> about how the name Mexicanos was being used where and at what time.

It occurs to me to wonder if the Caddo form means anything besides
'Frenchman'.  Any chance it means 'people who don't have a specific name'?