Oxford Dictionary definition-
Corn, Brit. any cereal before or after harvesting, the chief crop of a region, eg. wheat, oats etc.   US& Austral. maize.
Any the wiser Vic   
 
   
 
I am still not sure why it is called Crabble Corn Mill though instead of simply Crabble Mill maybe a marketing ploy or someone just thought it sounded better.