Buy the farm

To die, especially in a military aircraft crash. Informal euphemism for death; potentially insensitive Regional use: United States military, later general American English.

U.S. military slang recorded during the Korean War, with a secure 1952 example, and probably older in speech. It extends the much older military expression buy it, meaning to be killed. Proposed farm imagery includes military death benefits enabling a family to buy its farm and government compensation after an aircraft crash; the evidence does not establish one exclusive explanation, and the common crash-damages story should not be stated as certain.