What does "Unca" mean?

As in, how the Perfect Master Cecil Adams is often called “Unca Cecil”. I can’t find it on wikipedia or the dictionary sites, and google only gives me instances of Cecil and other people called this.

Is it a regional variant of Uncle? (Spanish would be diferent, wouldn’t it?)

Or does it mean something else?

Minor thing, I know, but I keep on wondering.

It’s means Uncle, it’s based off of Ducktales, it’s how Huey, Dewey and Lewey pronounced ‘Unca’ Scrooge.

It predates Ducktales by several decades, even for the fowl trio you mention. They also spend a lot of time interacting with Unca Donald in some much older Disney cartoons. And even that’s unlikely the first use ever.

OH! Well, both paper books of Donald & Co. and TV cartoons I get in Germany are all translated, so a lot of names are changed:
Donald’ nephews are Trick, Tick and Track
their boy scout troop is Fähnlein Fieselschweif
his uncle is “Onkel Dagobert” (a criminal called himself Dagobert because of this)
Gladstone Gander is Gustav Gans
the city is Entenhausen
Beagle boys are Panzerknacker (lit. safe crackers)
Gyro Gearloose is Daniel Düsentrieb (lit. jet thrust)
Magicia de Spell is Gundel Gaukley (Gaukelei is trick magic)
Flintheart Glomgold is Mac Moneysac (note that in the German version, Uncle Dagobert is also a Duck, not a MacDuck, though he is still of Scottish origin).