續一切經音義 7.125

7.125

噤口（上渠飲反字統云寒而口閉也說文云從口禁聲有作䫴怒而切齒也非噤口字也）。

噤口 (The upper character is pronounced with the fanqie qu + yin. The Zitong says: "Cold and having the mouth closed." The Shuowen says: "Classified under 'mouth' [口], with 禁 as phonetic." Some write it as 䫴, meaning gnashing teeth in anger, which is not the character for 噤口).