The oracle bone form of 冖 was a pictograph of a cloth or a cover with draping edges. It is one out of a set of three similar radicals (冖,宀 and 穴) collectively refered to as 宝盖头 (bǎo ɡài tóu) or "protection radicals", each referencing a protective covering. 冖 is called 秃宝盖头 (tū bǎo ɡài tóu), or the "bald proctection radical" because it resembles 宀 without the top stroke.
冖 is radical number 14 in the Chinese table of radicals. It is most often appears as a component character at the top of a word such as: 冠 (guàn, guān) "crown"， 冗 (rǒng) "redundant", 写 (xiè, xiě) "write", 军 (jūn) "military", 农 (nóng) "agriculture", and 冤 (yuān) "injustice".