blunt, stupid

鈍 is composed of 金 (metal) and 屯 (store up). 屯 is a pictograph of a plant as it sprouts, and its original meaning is the initial growth of plants. When all things first come into being, they are untempered and of weak strength. Therefore, 鈍 conveys the idea of a metal knife without a sharp edge, and means not sharp or blunt; it is also used to describe a dull or slow-witted person.