casement
/ˈkeɪsmənt/noun
1- a window or part of a window set on a vertical hinge so that it opens like a door竖铰链窗。
1.1
- chiefly poetic/literary a window〈主诗/文〉窗户。
1.2
- the sash of a sash window窗框。
词源
late Middle English (as an architectural term denoting a hollow moulding)： from Anglo-Latin cassimentum, from cassa, from Latin capsa （see CASE2）.