There seems to be a consensus from most dictionaries that the word semolina derives from the Italian semola, meaning "bran", which in turn comes from the Latin simila, meaning "fine flour". As bran and fine flour are basically opposites - does anyone know how this came to be?

If not - do you know any experts who I could consult with?

The ones at wordorigins did you just fine, I thought.

I did not chime in at WO mainly because I've been too busy to do the necessary research. My random thoughts and observations: (1) Latin far 'spelt' also meant course '(course) meal' (related to our word barley); farina 'flour', flos farina 'flower of meal', i.e., the best of the meal, the finer. A monolingual Italian dictionary I consulted said that semola means 'bran', although in some southern dialects it means 'flour'. The word is rare, only showing up in Celsus and Pliny. I took a look at the Celsus passage where he discusses simila. He groups it in with the "windy" foods which cause flatulence and ought to avoided. You might want to find Watkins' article "Let Us Now Praise Famous Grains" (if you're interested, I can look up the citation).

To add some to the confusion the French use 'semoule' for coursely grinded wheat flour and finely grinded rice and potatoe flour. For finely grinded wheat flour they use 'farine'.
Farine de maïs is not polenta (that would be semoule de maïs), but maïs starch and 'fleur de farine' is a very fine type of wheat flour.
I will spare you the dutch confusion.

That's interesting - is there any way to know whether the usage in southern dialects is more or less recent than the other dialects?

I found Watkins article - was there a particular passage that you thought was relevant?

Thanks to everyone for their help.

I finished my research and my post is up here:

http://www.balashon.com/2009/09/solet-and-semolina.html