When someone attempts to say, "Yeah, but (...)" etc, it will sound as though the two words are often combined into one, as if it were a small woodland animal. Hence, you obtain "Yeahbut". It is even more so funny when they say "fucking" afterwards, making it sound as though they plan on having intercourse with a small woodland animal.

A classic law school student -ism. Usually employed right before the speaker dives into an argument that has no sound basis in logic, reason, or this universe.