2indexing radical for characters built inside a downward-opening box
Tips
usage
冂 is sometimes nicknamed 同字框 (the 'same-character frame') because it forms the outline of 同, 网, 周, and 内. The frame opens downward, distinguishing it from the fully closed 囗 (#31).
history
Xinhua glosses 冂 as 远远的郊野 — the distant outskirts — and notes it is the proto-form of 扃 (door bolt). The character is never used as a free word in modern Chinese.
Radical
FrameKangxi #13
The downward-opening frame radical. A structural index slot covering characters whose outline is a three-sided box open at the bottom: 同, 网, 周, 冉, 内, 冒. Not standalone; useful only as a Kangxi lookup category and as a learner's hook for spotting frame-shaped characters.