Definition

1. Verb (intransitive):
   • To become unfit for consumption or use: To undergo a process of decay, decomposition, or deterioration, making something no longer suitable for its intended purpose, especially regarding food or perishable items.
   • To stop operating or functioning: To cease to work correctly; to break down or fail, often suddenly or completely.

Examples of Usage

• Verb (becoming unfit):
  • Milk will go bad if you leave it out of the refrigerator.
  • We need to eat these fruits before they go bad.
• Verb (stopping function):
  • The old television finally went bad and we had to buy a new one.
  • The hard drive in my computer went bad, and I lost all my files.

Advanced Usage

• "go bad on someone": Used informally to describe something failing or becoming unusable for a person, often at an inconvenient time.
  • My car went bad on me during the road trip.
• Describing abstract failure: While often physical, it can describe the failure of plans or situations.
  • The whole deal went bad after the investor pulled out.

Variants and Related Words

• Spoil (verb): To become unfit for use or consumption; to decay. Often used interchangeably with "go bad" for food.
  • The heat will spoil the meat.
• Rot (verb): To decompose or decay, typically used for organic matter.
  • The wood began to rot.
• Break down (phrasal verb): To cease to function (for machines or vehicles).
  • The elevator broke down.
• Fail (verb): To stop functioning normally; to be unsuccessful.
  • The engine failed.

Synonyms

• Deteriorate: To become progressively worse.
• Perish: (For food) to decay or rot.
• Give out: To stop working; to fail.
• Conk out: (Informal) to break down or stop working.

Related Phrasal Verbs

• Go off (UK English): Primarily used for food and drink meaning to become spoiled or sour.
  • I think the milk has gone off.
• Go down: (For computer systems or networks) to stop functioning.
  • The website went down for maintenance.

Related Idioms

• Go to the bad: An older idiom meaning to deteriorate morally or to ruin one's character. (Note: This is a distinct idiom and not a direct variant of "go bad").
  • He fell in with the wrong crowd and went to the bad.
• Turn bad: Similar to "go bad," meaning to become spoiled or to deteriorate.
  • The weather turned bad, so we cancelled the picnic.

Verb

1. become unfit for consumption or use
   • the meat must be eaten before it spoils
2. stop operating or functioning
   • The engine finally went
   • The car died on the road
   • The bus we travelled in broke down on the way to town
   • The coffee maker broke
   • The engine failed on the way to town
   • her eyesight went after the accident