'Bèiléi mào' literally combines three characters: 'bèi' (shell), 'léi' (thunder), and 'mào' (hat). Though the characters individually suggest 'shell-thunder-hat', this is a phonetic loan translation of the French word 'béret' — the 'bèi-léi' part approximates the French pronunciation, while 'mào' specifies it's a type of headwear. It refers specifically to the soft, round, flat-crowned, brimless woolen hat traditionally associated with French, Basque, and military culture.

The term is used in modern Chinese fashion, art, and media contexts, often evoking sophistication, creativity, or European style. Unlike generic terms like 'màozi' (hat), 'bèiléi mào' carries stylistic connotations and is rarely used for functional headgear like baseball caps or sun hats. It’s commonly seen in descriptions of outfits, fashion photography, and character illustrations — especially for artists, students, or chic urban figures.