Meaning of IQ in English

IQ

noun Etymology: intelligence quotient Date: 1920 a number used to express the apparent relative intelligence of a person: as, the ratio of the mental age (as reported on a standardized test) to the chronological age multiplied by 100, a score determined by one's performance on a standardized intelligence test relative to the average performance of others of the same age, proficiency in or knowledge of a specified subject

Merriam Webster. Explanatory English dictionary Merriam Webster.      Толковый словарь английского языка Мерриам-Уэбстер.