Cool MateConstant vs Eternal
When to use each in English, with meaning, register, and examples.
Constant
Top 2,000 (common)B2adjective
Eternal
FormalTop 3,000 (common)C1adjective
Most formal: EternalMost common: Constant
| Constant | Eternal | |
|---|---|---|
| Pronunciation | 🇬🇧 /["/ˈkɒnstənt/"]/🇺🇸 /["/ˈkɑːnstənt/"]/ | 🇬🇧 /["/ɪˈtɜːnl/"]/🇺🇸 /["/ɪˈtɜːrnl/"]/ |
| Meaning | Something that stays the same and doesn't change. | Lasting forever, never ending. |
| Example | She is a constant source of inspiration for her team. | Many religions speak of an eternal life after death. |
| Register | Neutral | Formal |
| How common | Top 2,000 (common) | Top 3,000 (common) |
| CEFR level | B2 | C1 |
| Part of speech | adjective | adjective |
| Collocations | be, remain, stay, fairly, reasonably, relatively, across, over, be, remain, stay, fairly, reasonably, relatively, across, over | eternal love, eternal life, eternal flame, eternal damnation, eternal bliss |
| Antonyms | variable, changing, inconstant | temporary, brief, finite |
| 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. | Confused with 'external', meaning outside., Using 'eternal' to describe short-lived events., Overusing in casual contexts. |
| Usage notes | 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 'eternal' in serious or literary contexts. It's appropriate for discussing concepts like love, life, or time but not typically used in casual conversation or everyday situations. |
Frequently asked questions: Constant vs Eternal
What's the difference between Constant and Eternal?
Constant: Something that stays the same and doesn't change. Eternal: Lasting forever, never ending.
Which is more formal: Constant and Eternal?
Eternal is the most formal of these.
Which is more common: Constant and Eternal?
Constant is the most common in everyday English.
Are Constant and Eternal the same CEFR level?
Constant: B2, Eternal: C1 on the CEFR scale.
Can I use Constant and Eternal interchangeably?
Not always. Constant and Eternal 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.