overcastadj.阴天的;阴暗的;愁闷的v.遮盖;(使)变暗;包边缝n.覆盖;阴天
overcast white-out密云性白视
overcast penetration穿过密云
overcast air-bridge上风桥
Overcast with heavy clouds浓云密布
overcast extent of organism微生物覆盖程度