A suffix added to a word to emphasize it, especially to refer to an abstraction of it. eg. grub (for food) becomes grubbage (the essence or concept of food)
Almost universally transforms to a non-count noun (you get a link cable, or some linkage, but not a linkage)
Yo, let's go score some grubbage, eh?
What kind of linkage do you have between these boxen?