booster chair

noun

plural booster chairs

: a portable seat that is placed on or attached to a chair or an automobile seat in order to raise a child to a higher position : booster seat

… high chairs let everyone eat together. The kids then graduate to booster chairs.

—Bill Rettew

If used properly, child safety seats (car seats, booster chairs, etc.) in cars and trucks reduce the risk of … injury …

—Steven M. Gursten

Word History

First Known Use

1950, in the meaning defined above