inflate

inflate — verb

1. to push air or gas into a hollow object so that it grows bigger and feels firmer

1.verbtransitive / intransitiveB1
Definition

to push air or gas into a hollow object so that it grows bigger and feels firmer, or to become bigger in this way because air or gas has been pushed in

Example

Soraya used a small pump to inflate the air mattress before her guests arrived.

transitive: inflate + object (mattress)

The tyres on Sumin's bicycle inflate through a valve on the wheel rim.

intransitive: tyres inflate through a valve

Common collocations
  • inflate a balloon
  • inflate a tyre
  • inflate a mattress
  • inflate with air
  • inflate with helium
Synonyms
  • pump up

    more informal; suggests using a pump, common for tyres and sports balls

  • blow up

    informal; can mean inflate with breath (balloons) or cause to explode

  • fill

    more general; does not specify that the filling causes expansion

Antonyms
  • deflate

    to let the air or gas out of something

Grammar Patterns

inflate + noun phrase

inflate + noun phrase + with + air/gas

noun phrase + inflate (intransitive)

Usage Note

This sense can be used transitively (someone inflates something) or intransitively (something inflates by itself). The past participle 'inflated' is commonly used as an adjective, e.g. 'an inflated tyre'.

Common Mistakes

I need to expand the balloons for the party.
I need to inflate the balloons for the party.
'expand' means to grow in general, while 'inflate' specifically means to fill with air or gas.

2. to describe or present something as being bigger, more valuable, or more signifi

2.verbtransitiveB2
Definition

to describe or present something as being bigger, more valuable, or more significant than the truth would justify

Example

The politician inflated the sales figures to make the project look more successful.

transitive: inflate + figures/numbers

Christopher felt the media was inflating the dangers of the new technology to attract viewers.

transitive: inflate + abstract noun (dangers, risks)

Common collocations
  • inflate figures
  • inflate claims
  • inflate importance
  • inflate ego
  • inflate achievements
Synonyms
  • exaggerate

    broader; can apply to any kind of overstatement, not just size or importance

  • overstate

    more formal; suggests going beyond the truth in a deliberate way

  • puff up

    informal; often used for someone's pride or ego

Antonyms
  • downplay

    to make something seem less important than it really is

  • understate

    to describe something as smaller or less significant than it is

Grammar Patterns

inflate + noun phrase (figures, claims, importance)

inflate + possessive + noun phrase

Usage Note

Often used with nouns related to numbers, status, or claims (figures, achievements, ego, importance, risks). The object is almost always abstract — you do not inflate a physical object in this sense.

Common Mistakes

The article inflated the facts' (when meaning 'the article contained wrong information').
The article inflated the importance of the facts, making them seem more dramatic than they were.
'inflate' suggests exaggeration of real things, not outright falsehood.

3. to make prices rise across an entire economy, or to rise in this way, typically

3.verbtransitive / intransitiveB2
Definition

to make prices rise across an entire economy, or to rise in this way, typically because the amount of money available increases or the value of currency drops

Example

The central bank's decision to print more money inflated the cost of everyday goods.

transitive: inflate + the cost of [goods]

Housing prices in the area inflated rapidly after the new train station was built.

intransitive: prices inflate

Common collocations
  • inflate prices
  • inflate costs
  • inflate the economy
  • inflate currency
  • inflate the money supply
Synonyms
  • push up

    more informal; can refer to a general or specific price rise

  • drive up

    suggests a force causing prices to rise, common in economic writing

Antonyms
  • deflate

    to cause prices to fall; opposite in economic contexts

Grammar Patterns

inflate + noun phrase (prices, costs)

noun phrase + inflate (intransitive: prices inflate)

Usage Note

This sense is primarily used in economic and financial contexts. It often appears in passive constructions ('prices were inflated by…') or with adverbs like 'sharply', 'rapidly', 'artificially'.

Common Mistakes

The shop inflated the price of milk last week.
The shop raised the price of milk last week.
For a single shop raising a single price, use 'raise' or 'increase'. 'Inflate' implies a broader, economy-wide or market-wide rise.

Word family

  • inflation
    nounB2
  • inflated
    adjectiveB2
  • inflatable
    adjectiveB1
  • inflater
    nounC1
  • deflate
    verbB2
  • deflation
    nounC1

Synonym discussion

Sense: verb/1

'Inflate' is the most neutral and precise term for filling something with air or gas, suitable for any register. 'Pump up' is informal and specifically implies using a pump — you pump up a tyre or a football, not a balloon you blow with your mouth. 'Blow up' is even more casual and ambiguous: it can mean inflating a balloon with breath or causing an explosion ('the bomb blew up'). 'Expand' is the broadest of the four and does not specify the mechanism — ice expands when it freezes, but you would never say 'ice inflates'. For learner clarity: use 'inflate' in formal writing ('the life jacket inflates automatically'), 'pump up' in casual conversation about sports gear ('I need to pump up my bike tyres'), and 'blow up' only for balloons or informal situations where the context makes the meaning obvious.

inflate ↗pump up ↗blow up ↗expand ↗

Common collocations

Nouns

Adverbs

Phrases

  • inflate the value of
  • inflate the cost of
  • inflate the importance of
  • inflate with pride

Prepositions

Etymology

LatinEnglish

'Inflate' comes from the Latin word 'inflare', which means 'to blow into'. It is formed from 'in-' (into) and 'flare' (to blow). English adopted the word in the early 1500s, first with the literal meaning of filling something with air. By the late 1600s, people were using it figuratively to describe someone's ego or reputation being 'puffed up'. The economic meaning — a general rise in prices — developed in the 1800s as modern banking and currency systems grew more complex.