sill
noun /sɪl/
/sɪl/
- (also windowsill, window ledge)a narrow shelf below a window, either inside or outside
窗沿；窗台 - a piece of metal that forms part of the frame of a vehicle below the doors
（车体的）门槛
词源Old English syll, sylle ‘horizontal beam forming a foundation’, of Germanic origin; related to German Schwelle ‘threshold’.