go off
4 meanings
make a sudden loud sound (an alarm, phone, or bomb)
What does "go off" mean in this sense?
Examples
- The fire alarm went off in the middle of the night and woke everyone up.
- Let's hope the smoke alarm doesn't go off while we're cooking.
- The bomb went off just seconds after the building was evacuated.
How to use it
The most common structure — the device is the subject and there is no object, since this phrasal verb is intransitive.
The smoke alarm went off as soon as she started frying the bacon.
Often used with time phrases to say when the signal happened or will happen.
My alarm went off at half past six, but I hit snooze twice.
Very commonly used in conditional and time clauses to describe what happens when a device triggers.
If the fire alarm goes off, everyone must leave the building immediately.
Used to describe perceiving the sound of a device activating — 'go off' follows the object in this structure.
Did you hear the car alarm go off last night? It was incredibly loud.
Common Collocations
Common Mistakes
'Go on' means something starts working steadily, like a light or heating system. 'Go off' describes a sudden triggering moment, like an alarm sounding. These are easy to mix up, but they have very different meanings.
In this sense, 'go off' is intransitive — it never takes an object. The device is always the subject, and nothing comes after 'off'.
The same phrase 'go off' has different meanings depending on the subject. With a device or alarm as the subject, it means emit a sudden noise or signal. With food as the subject, it means go bad. Always check what the subject is.
Usage
This sense is neutral and works in both spoken and written English. The subject is always a device, alarm, or explosive — never a person.
explode (a bomb) or fire (a gun)
Sense 2: What does "go off" mean?
Examples
- A bomb went off in the city centre, injuring several people.
- They could hear grenades going off somewhere in the distance.
- The gun went off accidentally while he was cleaning it.
How to use it
The bomb, gun, grenade, or similar device is always the grammatical subject — a person can never be the subject in this sense.
A car bomb went off near the central train station early this morning.
Adverbs of manner are commonly added to describe how or why the explosion or discharge happened.
The gun went off accidentally when he stumbled on the stairs.
A prepositional phrase of place is often added to say where the explosion or shot occurred.
They heard fireworks going off somewhere in the distance.
A time expression can be added to specify when the device exploded or the gun was fired.
The grenade went off seconds after they had taken cover.
Common Collocations
Common Mistakes
The weapon or explosive must be the grammatical subject. It is always the bomb, gun, or grenade that 'goes off', never the person handling or firing it.
'Go off' in this sense is intransitive, so it cannot be followed by an object. Nothing comes directly after 'go off' except optional adverbs or prepositional phrases.
'Go off' has several different meanings in English — food can go off (spoil), an alarm can go off (activate), or someone can go off something (stop liking it). Context and subject make the explosion sense clear: only weapons, bombs, and explosives 'go off' in this sense.
Usage
This phrasal verb is neutral in register and appears frequently in news reports and fiction. It is always intransitive, so no object follows — the bomb, gun, or explosive is always the grammatical subject.
stop liking someone or something you used to enjoy
Sense 3: What does "go off sb/sth" mean?
Examples
- I've gone off coffee lately — I just don't enjoy it the way I used to.
- She went off him after he cancelled their plans three times in a row.
- Have you gone off the idea of moving abroad, or are you still thinking about it?
How to use it
The most common pattern — a person stops liking a thing or another person, with the object placed directly after 'off'.
I've completely gone off reality TV — I find it so tedious now.
Pronouns replace the noun object and follow 'off' directly, just as noun objects do.
She used to love that podcast, but she's gone off it recently.
When the thing you stop liking is an activity, it is expressed as a gerund after 'off'.
He's gone off running since the weather turned cold.
Abstract nouns like 'idea', 'plan', or 'concept' work naturally as objects when someone loses enthusiasm for a proposal or intention.
We've gone off the idea of renting — we'd rather save up and buy instead.
Common Collocations
Common Mistakes
When a person is the subject, 'go off something' means to stop liking it. When food or drink is the subject, 'go off' means it has spoiled. The subject of the sentence makes all the difference.
'Go off' in this sense is inseparable — the object must always come after 'off', never between 'go' and 'off'.
Because 'go off' describes a gradual, often involuntary change in feeling, using 'will go off' to predict it sounds unnatural. Stick to present perfect or past simple.
Usage
This is British English — American English speakers rarely use 'go off' in this sense. It most naturally appears in the present perfect ('I've gone off...') to describe a change in taste that has happened recently.
become bad and not safe to eat or drink
Sense 4: What does "go off" mean?
Examples
- Don't drink that milk — I think it's gone off.
- The chicken went off because I left it out of the fridge overnight.
- Does this cream smell like it's going off to you?
How to use it
The food or drink is always the subject — this verb has no object, so you cannot put anything between 'go' and 'off'.
The yoghurt has gone off — don't eat it.
The present perfect is the most natural choice when you have just discovered that something is no longer good.
I think the cream has gone off — it smells terrible.
Use the simple past to talk about a specific moment or period in the past when the food became bad.
The leftovers went off because I forgot to put them in the fridge.
Use a modal verb to talk about the possibility of food becoming bad in the future.
That fish might go off if you leave it out in this heat.
This extended pattern is very natural when you are describing a sensory clue that suggests the food is no longer good.
This butter tastes like it's gone off — when did you buy it?
Common Collocations
Common Mistakes
When the food is the subject ('the meat has gone off'), it means the food has spoiled. When a person is the subject with food as the object ('I've gone off meat'), it means they no longer enjoy it — a completely different meaning. Pay close attention to who or what comes before 'go off'.
Avoid saying 'is going off' when you mean food is spoiling — in most contexts this sounds like an alarm or phone is making a noise. Stick to the present perfect or simple past for the spoilage meaning.
Because the food itself is the subject, you cannot add an object. You cannot 'go off' something in this sense — the food does the going off by itself.
Usage
This meaning is common in British and Australian English; American speakers usually say 'go bad' or 'spoil' instead. The present perfect ('has gone off') is the most natural tense, often used when you discover the food is no longer good.
Frequently Asked Questions
Can 'go off' be used in the passive, like 'the alarm was gone off'?
No — 'go off' in this sense cannot be made passive. Because there is no object in the sentence, there is nothing to turn into a subject for a passive structure. You can only say 'The alarm went off.'
Does 'go off' always mean an alarm or signal? I've seen it used in other ways.
No, 'go off' has several different meanings in English. In this sense, the subject is always a device, alarm, or timer making a sudden noise or signal. Other meanings are covered separately on this platform — look out for the sense labels to know which one you're studying.
What kinds of things can 'go off' in this sense?
The subject is usually a device that produces a sudden sound or flash as a signal — things like alarm clocks, smoke alarms, fire alarms, car alarms, sirens, timers, and beepers. You can also use it metaphorically, for example: 'A bell went off in my head' meaning you suddenly remembered or realised something.
Is it natural to use 'go off' in present tenses, or only past?
It works naturally in many tenses. The simple past is common for describing events ('The alarm went off'), but the simple present and conditionals are also very natural ('If the alarm goes off, call me'). The future with 'will' also works well: 'The timer will go off in ten minutes.'
Does 'go off' suggest that the explosion was an accident?
It depends on what is going off. With firearms, 'go off' often implies the shot was unintentional — for example, a gun 'going off' when dropped. With bombs and grenades, the verb is more neutral and simply describes the moment of detonation, without implying whether it was deliberate or accidental.
Can I use 'go off' in the present continuous — like 'The bomb is going off right now'?
This is unusual because an explosion is a sudden, instantaneous event rather than an ongoing process. The past simple ('the bomb went off') and past continuous for background events ('bombs were going off all around them') are far more natural. Reserve the present continuous for narrative effect in fiction, not for describing an explosion in real time.
What is the difference between 'go off' and 'blow up' when talking about explosions?
'Go off' is always intransitive and focuses on the device itself triggering or detonating — the bomb, mine, or grenade is always the subject. 'Blow up' can be used transitively, meaning someone caused the explosion ('they blew up the bridge'), or intransitively. When you want to highlight the event of detonation with the device as subject, 'go off' is the more precise and natural choice.
Can 'go off' describe fireworks as well as bombs and guns?
Yes — fireworks 'going off' is a very natural and common use of this phrasal verb. Fireworks are treated similarly to explosives, and the same pattern applies: the fireworks are the subject and no object follows ('the fireworks went off at midnight').
Is 'go off' used more in British or American English for this meaning?
This sense of 'go off' is used in both British and American English with no significant difference in frequency or meaning. You will find it in news reports, fiction, and everyday conversation on both sides of the Atlantic.
Is 'go off' in this sense used in American English?
Not really — this is a distinctly British English usage. American English speakers are unlikely to use 'go off' to mean stop liking something. They would more naturally say 'I've lost my taste for it' or 'I'm not really into it anymore'.
Does 'go off' always mean the change happened gradually?
Usually, yes — it tends to suggest a slow, almost unexplained shift in preference rather than a sudden decision. That said, it can also describe a fairly quick change, especially if something specific triggered it, like 'She went off him after he let her down'.
Can I use 'go off' without an object — for example, just 'I've gone off'?
It's best to always include the object in this sense. Without one, 'go off' could easily be misread as one of its other meanings, such as an alarm sounding or food spoiling. Keeping the object makes your meaning clear.
Why does 'go off' so often appear with the present perfect?
Because it describes a change that happened at some point in the past and is still true now — exactly what the present perfect is used for. Saying 'I've gone off spicy food' means the change happened recently and you still feel that way. The past simple works too, but usually in storytelling: 'I went off fizzy drinks when I started at the gym'.
Can 'go off' be used about a person, not just food or hobbies?
Yes, absolutely. You can go off a friend, a colleague, or a celebrity just as naturally as going off a food or hobby. For example, 'I've gone off that actor since I read that interview about him' is perfectly natural British English.
Is 'go off' (for food) used in American English?
It's not very common in American English. Americans usually say 'go bad', 'spoil', or 'turn' instead (e.g. 'the milk has gone bad'). 'Go off' in this sense is mainly British and Australian English, so if you're speaking with American speakers, 'go bad' might sound more natural to them.
What kinds of food can 'go off'?
Typically, perishable foods and drinks — things like milk, meat, fish, chicken, eggs, cheese, cream, yoghurt, and leftovers. These are all things that can spoil if not stored correctly or if left out too long. You wouldn't normally say a tin of biscuits or a bag of sugar has 'gone off'.
Can I use 'go off' to talk about food that is slightly bad, or only completely spoiled food?
You can use it for both. You might say something has 'slightly gone off' or 'just starting to go off' for food that isn't completely bad yet but is no longer at its best. The phrase is flexible enough to cover anything from mildly stale to completely inedible.
Does 'go off' have other meanings? I've seen it used in different ways.
Yes, 'go off' has several different meanings in English. This page covers only the food spoilage sense. Other senses include alarms or phones making a noise, and a British English expression for no longer liking something. The subject of the sentence usually makes the meaning clear — if it's a food item, it's almost certainly the spoilage sense.
Which tense should I use most often with this meaning?
The present perfect ('has/have gone off') is the most natural choice, especially when you've just discovered that something is bad — for example, opening the fridge and realising the milk is spoiled. The simple past ('went off') works well when explaining what happened, and modal verbs like 'might go off' or 'could go off' are useful for warnings about food that might spoil soon.
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