ballast
US /ˈbæl.əst/
UK /ˈbæl.əst/
名詞
1.
鎮流器
heavy matter such as sand, stone, or water that is used at the bottom of a ship or a hot-air balloon to make it heavier, or the small stones on which railroads and roads are made:
範例:
•
The weed may have been accidentally imported in soil used as ship ballast.
在 Lingoland 學習這個單詞