noun Date: circa 1895 a descriptive clause that is essential to the definiteness of the word it modifies (as that you ordered in “the book that you ordered is out of print”)
RESTRICTIVE CLAUSE
Meaning of RESTRICTIVE CLAUSE in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012