6 vacant

1 not filled or occupied; empty 未占满的; 未占用的; 空著的
    Is the lavatory vacant? 厕所里没有人吧?
    a vacant situation, post, hotel room 空著的职务、 空缺的职位、 旅店的空房间. =>Usage at empty1 用法见empty1.
(a) showing no sign of thought or intelligence; blank 无思想或智慧的; 木然的
    a vacant stare, look, etc 茫然的凝视、 目光等.
(b) empty of thought (思想)空虚的
    a vacant mind 空荡荡的头脑. > vacantly adv
    stare, look, gaze, etc vacantly into space 木然地注视、 观望、 凝视...著空间.