Age vs Century

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

Age

Top 1,000 (very common)A1noun

Century

Top 1,000 (very common)A1noun
 AgeCentury
Pronunciation🇬🇧 /["/eɪdʒ/"]/🇺🇸 /["/eɪdʒ/"]/🇬🇧 //ˈsɛnʧəri//🇺🇸 //ˈsɛnʧəri//
MeaningThe number of years someone has lived.A period of 100 years.
ExampleHer age is just a number.The 21st century started in the year 2001.
RegisterNeutralNeutral
How commonTop 1,000 (very common)Top 1,000 (very common)
CEFR levelA1A1
Part of speechnounnoun
Collocationsearly, tender, young, attain, get to, live to, group, range, limit, at a/​the age, between the ages, by the age, the age of consent, somebody’s own age, years of age, spend, take, absolutely ages, ages ago, for ages, early, tender, young, attain, get to, live to, group, range, limit, at a/​the age, between the ages, by the age, the age of consent, somebody’s own age, years of age, another, bygone, different, during the… age, in a/​the age, through the ages, in this day and age21st century, mid-century, turn of the century
Antonymsyouth, childhoodmoment, instant
Common mistakesUsing 'age' as a verb incorrectly, e.g., 'I age 25.', Confusing 'age' with 'stage', e.g., 'In this stage of my life.', Saying 'more old' instead of 'older.'Confused with 'decade', which means 10 years., Using 'centuries' incorrectly as a singular noun.
Usage notesUsed in both informal and formal contexts. Be careful not to confuse 'age' with phrases like 'young' or 'old' when describing someone.Use 'century' when discussing historical periods or time. Avoid using it in casual contexts unrelated to time.

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Century

Frequently asked questions: Age vs Century

What's the difference between Age and Century?

Age: The number of years someone has lived. Century: A period of 100 years.

Are Age and Century the same CEFR level?

Age: A1, Century: A1 on the CEFR scale.

What part of speech are Age and Century?

Age: noun, Century: noun.

Can you show an example of each?

Age: Her age is just a number. Century: The 21st century started in the year 2001.

Can I use Age and Century interchangeably?

Not always. Age and Century 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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