mass noun
1
- heavy material, such as gravel, sand, iron, or lead, placed in the bilge of a ship to ensure its stability（碎石、沙、铁或铅等）压舱物。
1.1
- a similar substance carried in an airship or on a hot-air balloon to stabilize it and jettisoned when greater altitude is required（飞机或热气球保持稳定的）镇重物（升高时可抛弃）。
1.2
- figurative something that gives stability or substance〈喻〉稳定因素; 实质内容：
the film is an entertaining comedy with some serious ideas thrown in for ballast.
这部影片是娱乐喜剧, 添加了一些严肃有意义的内容压台。
2
- gravel or coarse stone used to form the bed of a railway track or the substratum of a road（作为铁道或公路路基的）道砟。
2.1
- a mixture of coarse and fine aggregate for making concrete（拌制混凝土的）石渣。
3
- count noun a passive component used in an electric circuit to moderate changes in current（电路中的）镇流器。
with obj. (一般作be ballasted)
1
- give stability to (a ship) by putting a heavy substance in its bilge给（船）装压舱物。
2
- form (the bed of a railway line or the substratum of a road) with gravel or coarse stone给…铺道砟。
短语
in ballast
- (of a ship) laden only with ballast（船）只装有压舱物。
词源
mid 16th cent.: probably of Low German or Scandinavian origin.