ceiling
/ˈsi:lɪŋ; `silɪŋ/ n
1 top inner surface of a room 天花板; 顶篷
Mind you don't bump your head on the low ceiling. 天花板很低, 留神别碰头.
2 cloud level 云幕高度.
3 maximum altitude at which a particular aircraft can normally fly 一航空器所能飞的最高限度; 升限; 上升限度
an aircraft with a ceiling of 20000 ft 一架能飞20000英尺高的飞机.
4 upper limit 上限: The government has set a wages and prices ceiling of 10%. 政府规定工资和物价提高的最高限度为10%.
5 (idm 习语) hit the ceiling/roof => hit 1.