Constant vs Fixed

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

Constant

Top 2,000 (common)B2adjective

Fixed

Top 1,000 (very common)B1adjective
Most common: Fixed
 ConstantFixed
Pronunciation🇬🇧 /["/ˈkɒnstənt/"]/🇺🇸 /["/ˈkɑːnstənt/"]/🇬🇧 /["/fɪkst/"]/🇺🇸 /["/fɪkst/"]/
MeaningSomething that stays the same and doesn't change.Something that is not changed or is repaired.
ExampleShe is a constant source of inspiration for her team.These fixed prices give farmers a degree of financial security.
RegisterNeutralNeutral
How commonTop 2,000 (common)Top 1,000 (very common)
CEFR levelB2B1
Part of speechadjectiveadjective
Collocationsbe, remain, stay, fairly, reasonably, relatively, across, over, be, remain, stay, fairly, reasonably, relatively, across, overbe, seem, become, very, firmly, securely, be, seem, become, very, firmly, securely
Antonymsvariable, changing, inconstantbroken, loose, unsteady
Common mistakes'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 'fixed' with 'fixated', which means to be obsessed., Using 'fixed' in the wrong tense, like saying 'I fix the problem' instead of 'I fixed the problem.', Misplacing 'fixed' in a sentence, leading to unclear meaning.
Usage notesUse '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 'fixed' when something has been repaired or when it's stable and unchanging. Avoid in casual conversations unless referring to repairs or adjustments.

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Fixed

Frequently asked questions: Constant vs Fixed

What's the difference between Constant and Fixed?

Constant: Something that stays the same and doesn't change. Fixed: Something that is not changed or is repaired.

Which is more common: Constant and Fixed?

Fixed is the most common in everyday English.

Which is more advanced: Constant and Fixed?

Constant is the highest level, at B2, on the CEFR scale.

Are Constant and Fixed the same CEFR level?

Constant: B2, Fixed: B1 on the CEFR scale.

What part of speech are Constant and Fixed?

Constant: adjective, Fixed: adjective.

Can you show an example of each?

Constant: She is a constant source of inspiration for her team. Fixed: These fixed prices give farmers a degree of financial security.

Can I use Constant and Fixed interchangeably?

Not always. Constant and Fixed 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.

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