noun
attic; garret
A French loanword for an attic or garret, often with a slightly stylish or European feel. Less common than native terms like 屋根裏.
from French grenier
パリのアパルトマンには、よくグルニエがある。
Parisian apartments often have an attic.
彼はグルニエを書斎に改装した。
He converted the garret into a study.