Originally Posted By: bexter
a type of processed filler of "meat" that comes in squares the same size as bagged bread! (no offense intended!)


That's about it. It's just a name for a class of food-like substances. You can certainly make sandwiches without "sandwich meat". You can take a turkey carcase, slice off some breast meat, and put it between a couple of slices of bread along with whatever else you want in there. You can do a lot of things.