Definition of “go off” - English Dictionary

“go off” in British English

See all translations

go off

phrasal verb with go uk /ɡəʊ/ us /ɡoʊ/ verb present participle going, past tense went, past participle gone


B1 If a light or a machine goes off, it stops working:

The lights went off in several villages because of the storm.

More examples

  • The damage to the fuse box caused the power to go off.
  • The light goes off when the batteries are flat.
  • The match had to be abandoned when the floodlights went off.
  • The electricity will be going off for ten minutes while the workmen test the circuit.
  • It's getting cold. The heater must have gone off.


C1 If a bomb goes off, it explodes:

The bomb went off at midday.

C1 If a gun goes off, it fires:

His gun went off accidentally.

More examples

  • The firework went off in his face.
  • They could hear the sound of bombs going off in the background.
  • The explosives went off without warning.
  • We must clear the area before the bomb goes off.
  • Do not move until you hear the starting pistol go off.


B2 UK If food or drink goes off, it is not good to eat or drink any more because it is too old:

This bacon smells a bit funny - do you think it's gone off?
See also

More examples

  • Put the milk back in the fridge or else it will go off.
  • That meat looks like it's gone off.
  • Cream will go off very quickly if it is not kept in the fridge.
  • Preservatives are added to prevent food from going off so quickly.
  • Food that is not stored correctly goes off more quickly.


B2 If a warning device goes off, it starts to ring loudly or make a loud noise:

The alarm should go off automatically as soon as smoke is detected.
Didn't you hear your alarm clock going off this morning?

More examples

  • They could hear the fireworks going off in the distance.
  • His car alarm is always going off by mistake.
  • I got a real shock when the fire alarm went off.
  • Take the chicken out of the oven when the timer goes off.
  • A buzzer goes off if the door has been left open.

(Definition of “go off” from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)

“go off” in American English

See all translations

go off

phrasal verb with go us /ɡoʊ/ verb present tense goes, present participle going, past tense went /went/ , past participle gone /ɡɔn, ɡɑn/

to explode, or to fire bullets:

The deer ran away just before the hunter’s gun went off.

If a special signal or an electronic device goes off, it warns people that there is danger or that something is wrong:

What do they do if the metal detector goes off?

(Definition of “go off” from the Cambridge Academic Content Dictionary © Cambridge University Press)