noun Date: 1910 a measure used in psychological testing that expresses an individual's mental attainment in terms of the number of years it takes an average child to reach the same level
MENTAL AGE
Meaning of MENTAL AGE in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012