You can figure out what this means. But maybe you can't, and if that's the case, it is:
... paste-like and batter-like poultry product produced by forcing bones, with attached edible tissue, through a sieve or similar device under high pressure to separate bone from the edible tissue.Mmmmm!
Bologna, according to the USDA, is a hot dog (I take issue with that, but that's beside the point). So, according to the USDA, bologna can contain any amount of mechanically separated chicken or turkey but no more than 20% mechanically separated pork.
Fortunately, mechanically separated meat (MSM) must be labeled as such in the ingredients statement.
Not for fortunately, mechanically separated meat probably contains lower-quality protein than that found in meat from muscle tissue, and bone marrow, so it's higher in fat and cholesterol. Not to mention that it's just plain old gross-sounding.
Makes you want to go out and try that bologna bubble gum, doesn't it?