derived from the root word bownt originating from the west coast valley girl vernacular. "Bowmpernickel" takes bownt one degree further, meaning- an abnormally negative reaction to a given circumstance. closely related to such words as "dang" or "awww, heck" or puhh.
person 1 says- "your flight's been cancelled."
person 2 says- "bowmpernickel."