画地图

画地图

Literally means:

draw map on the sheet

Actually means:

wet the bed

It means figuratively wetting the bed,i.e., urinating involuntarily on bed while asleep. It also refers to children urinating on others or the bed. (The word"map"derives from the urine stain that takes an irregular shape like a map). Used jocularly or as euphemism.

比喻尿床，即睡觉时不由自主地在床上遗尿，也小孩子撒尿在人身上或者床上等。尿湿的地方呈不规则形状，有点像地图，所以叫做画地图。含委婉、风趣的意味。