eat one's head off

Meanings:

• 1.

  generalliteral
  • To bite off or consume the head of something; a literal and usually hyperbolic image of eating a head.

• 2.

  British EnglishAmerican Englishhistoricaldatedidiomatic
  • Of an animal: to cost more to feed or maintain than the animal is worth; to be uneconomical to keep because it consumes excessive provisions.