(1) [the younger brother]∶弟弟
(2) [young man]∶年长者对年青人的客套称呼
阿弟,就是这辆车,在楼上我讲的就是这辆车。
There she is , Buddy , just like I told you upstairs .
阿弟,把你弟从洗碗机里捞出来
Get your brother off the dishwasher !