out of the corner of one's eye
without looking at sb.or sth.directly or openly从眼角处看;窥伺
The cat looked at the mouse out of the corner of its eye.猫暗地里注视着老鼠。
As the little boy spoke to his mother,he looked out of the corner of his eye at his elder brother waving to him from outside the window.那个小男孩在跟他母亲说话时,用眼梢瞟着站在窗外向他招手的哥哥。