ullage

n.不足量,损耗

（尤指容器中未占满的）空隙，空间；

名词；

1、There is a small ullage at the top of the wine bottle.
酒瓶顶部有一个小的空隙。

2、The tank had an ullage of about 10%.
油罐的剩余空间大约为10%。