what is the meaning of top up

top-up:
1. 補貼(正常收入以外的)
A sum of money added to what you already have to increase it to the amount you need
2. (重新斟滿杯子的)補充飲料
An amount of a drink that you add to a cup or glass to make it full again

top up chinese mean

1. 將(未滿的容器)裝滿

english mean

fill up