seize up

suddenly stop working or moving (a machine or part of the body)

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What does "seize up" mean?

To seize up means to stop working completely and suddenly, because something has jammed, locked solid, or become too stiff to move. The term applies most naturally to engines and mechanical parts that fail due to friction, overheating, or a lack of lubrication, but it is equally at home describing human joints, muscles, or a back that locks up after exertion or exposure to cold. A key feature of seize up is that it implies a total, abrupt halt rather than a gradual slowing — something that was functioning simply stops. Journalists and commentators also use it figuratively to describe larger systems — an economy, a set of negotiations, or urban traffic — that have ground entirely to a standstill. The subject is always the thing that stops working; nothing is done to it from the outside.

Examples

How to use it

subject (machine/body part) + seize up

The most fundamental pattern: the thing that stops working is always the subject, and no object follows.

The gearbox seized up without any warning, and the car had to be towed away.

subject + seize up + in/after/without + circumstance

A prepositional phrase often follows to explain the trigger — cold, overuse, neglect, or lack of lubrication.

Her knee seized up after the second hour of the hike, forcing her to rest.

subject + completely/suddenly + seize up

Adverbs like 'completely' or 'suddenly' frequently accompany the verb to emphasise the totality or abruptness of the failure.

The pump suddenly seized up, bringing the entire production line to a halt.

subject (system/process) + seize up

Used figuratively in journalism and formal writing when a large-scale system or process grinds to a complete halt.

Supply chains seized up during the crisis, leaving retailers with empty shelves.

tend to / can + seize up

Modal and semi-modal constructions work well for general or habitual statements about conditions that cause this kind of failure.

Older engines tend to seize up if you neglect regular oil changes.

Common Collocations

enginebackjointsgearboxmusclesentire system

Common Mistakes

Using it as a transitive verb

'Seize up' is intransitive — the thing that stops working must be the subject, not the object. You cannot say that something seizes up another thing.

✗ The cold seized up the pipes overnight.
✓ The pipes seized up in the cold overnight.
Confusing it with 'freeze up'

Both describe something stopping, but 'freeze up' emphasises cold temperatures or psychological paralysis, whereas 'seize up' points to mechanical jamming, friction, or physical stiffening from overuse. They overlap, but are not always interchangeable.

✗ My back froze up after I lifted all those boxes — the joints just won't move.
✓ My back seized up after I lifted all those boxes — the joints just won't move.
Dropping 'up' from the phrasal verb

'Up' is an essential part of this verb and cannot be removed. 'The engine seized' has a different or incomplete meaning in most contexts.

✗ The machinery seized during the night shift.
✓ The machinery seized up during the night shift.

Usage

Equally common in both British and American English. Beyond machines and bodies, 'seize up' is frequently used in journalism to describe systems, economies, or negotiations that have ground to a halt.

Frequently Asked Questions

Can 'seize up' be used in the present continuous — like 'the engine is seizing up'?

It's possible but uncommon. 'Seize up' typically describes a completed, sudden event, so the simple past or present perfect are far more natural. The present continuous works only if you're describing a failure happening in real time right before your eyes — 'Listen — I think the engine is seizing up right now' — but this is a rare situation.

Can I use 'seize up' to describe people, or is it only for machines?

It's very naturally applied to human bodies — especially backs, joints, muscles, and knees that become too stiff to move after exertion or cold. 'My back seized up completely after the move' is perfectly idiomatic. The key is that it describes a sudden physical lockup, not general pain or tiredness.

Does 'seize up' always imply something went wrong, or can it describe something working as intended?

'Seize up' almost always implies an unwanted failure or breakdown — it carries a negative connotation of something going wrong. It would not be used to describe, say, a brake engaging properly; for that you'd use a different verb like 'lock' or 'engage'.

Can 'seize up' be used for abstract things like negotiations or an economy?

Yes, and this is a well-established figurative use, especially in journalism and formal writing. When negotiations, a financial system, or traffic 'seize up', the implication is a complete and sudden halt — not a gradual slowdown. It's the same core idea of something that was functioning suddenly locking solid.

Is 'seize up' more British or more American English?

It's used equally in both British and American English with no significant regional preference. You'll encounter it in automotive, medical, economic, and journalistic contexts on both sides of the Atlantic.

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