This radical is understood as an identical variant of "person" 人, and shows a person who stands with the legs apart. - This radical has several varation, i.e. a lying person , a sitting 匕 person.
This radical gets its meaning by the similarity to the character for arrow: 箭 (jiàn), which has a similar body under the bamboo 竹. Due to the pointed top this radical is understood as the arrow's head 人 that goes into the flesh 月/肉 and cuts刂.
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