Chronic vs Constant vs Persistent

When to use each in English, with meaning, register, and examples.

Chronic

Top 2,000 (common)C1adjective

Constant

Top 2,000 (common)B2adjective

Persistent

Top 2,000 (common)C1adjective
 ChronicConstantPersistent
Pronunciation🇬🇧 /["/ˈkrɒnɪk/"]/🇺🇸 /["/ˈkrɑːnɪk/"]/🇬🇧 /["/ˈkɒnstənt/"]/🇺🇸 /["/ˈkɑːnstənt/"]/🇬🇧 /["/pəˈsɪstənt/"]/🇺🇸 /["/pərˈsɪstənt/"]/
Meaninghappening all the time or for a long timeSomething that stays the same and doesn't change.Continuing to do something despite difficulties.
Examplechronic bronchitis/arthritis/asthmaShe is a constant source of inspiration for her team.She showed persistent effort in completing the project despite numerous obstacles.
RegisterNeutralNeutralNeutral
How commonTop 2,000 (common)Top 2,000 (common)Top 2,000 (common)
CEFR levelC1B2C1
Part of speechadjectiveadjectiveadjective
Collocationschronic illness, chronic pain, chronic condition, chronic fatigue, chronic diseasebe, remain, stay, fairly, reasonably, relatively, across, over, be, remain, stay, fairly, reasonably, relatively, across, overbe, extremely, incredibly, really, be, extremely, incredibly, really
Antonymsacute, temporary, short-termvariable, changing, inconstanttemporary, yielding, intermittent
Common mistakesConfused with 'acute', which means a condition that comes on quickly., Using it to describe minor or temporary issues instead of serious ones., Forgetting to connect it with a noun, as in 'chronic pain' or 'chronic illness'.'Constant' confused with 'constant' meaning an unchanged quantity in mathematics., 'Constantly' used incorrectly as an adjective instead of adverb., 'Constants' misused in plural form when referring to singular concepts.Confusing with 'consistant' which means something different., Using 'persistent' in a positive context only; it can also refer to annoying behavior., Mispronouncing the word, especially the 's' sound.
Usage notesUsed in medical contexts to describe conditions that are long-lasting. Avoid in casual conversations where simpler words (like 'constant') might be more appropriate.Use 'constant' when discussing something that remains unchanged over time. It can be used in both formal and informal contexts, but is often used in academic or scientific discussions.Use 'persistent' in texts where determination or refusing to give up is highlighted. It's more appropriate in formal or neutral contexts, while not commonly used in casual conversation.

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Persistent

Frequently asked questions: Chronic vs Constant vs Persistent

What's the difference between Chronic, Constant, and Persistent?

Chronic: happening all the time or for a long time Constant: Something that stays the same and doesn't change. Persistent: Continuing to do something despite difficulties.

Are Chronic, Constant, and Persistent the same CEFR level?

Chronic: C1, Constant: B2, Persistent: C1 on the CEFR scale.

What part of speech are Chronic, Constant, and Persistent?

Chronic: adjective, Constant: adjective, Persistent: adjective.

Can you show an example of each?

Chronic: chronic bronchitis/arthritis/asthma Constant: She is a constant source of inspiration for her team. Persistent: She showed persistent effort in completing the project despite numerous obstacles.

Can I use Chronic, Constant, and Persistent interchangeably?

Not always. Chronic, Constant, and Persistent are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.