mental age

American  

noun

Psychology.

1. the level of native mental ability or capacity of an individual, usually as determined by an intelligence test, in relation to the chronological age of the average individual at this level.

   a ten-year-old child with the mental age of a twelve-year-old; a mental age of twelve.

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mental age British  

noun

1. psychol the mental ability of a child, expressed in years and based on a comparison of his test performance with the performance of children with a range of chronological ages See also intelligence quotient

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Etymology

Origin of mental age

First recorded in 1910–15

Compare meaning

How does mental-age compare to similar and commonly confused words? Explore the most common comparisons:

• mental age vs. chronological age

Example Sentences

He wanted to know exactly what had happened, but could not ask Aaron, who is non-verbal and whom he describes as having the mental age of a two-year-old.

From BBC • Jul. 15, 2025

It’s not cute watching and adult man regress to the mental age of a three-year-old.

From Salon • Mar. 1, 2024

Her mental age was about 5 or 6 years old, her parents said in the claim.

From Fox News • Jan. 21, 2020

They also argued his sentence was unconstitutional because although he was 18 at the time of the killing, his mental age and maturity lagged behind his actual age.

From Washington Times • May 4, 2018

Our analysis of the responses of nearly 1500 subjects shows that improvement with increasing mental age is steady and fairly rapid.

From The Measurement of Intelligence An Explanation of and a Complete Guide for the Use of the Stanford Revision and Extension of the Binet-Simon Intelligence Scale by Cubberley, Ellwood Patterson