pluck, pick, tear, (kokuji)
毟 centers on pulling something away with force: plucking feathers or hair, picking something off, or tearing something out. It is a Japanese kokuji created for this specific action.
毟 is a Japanese kokuji, created by combining 少 (few, little) and 毛 (hair) to express the action of plucking or pulling out hair or feathers. The exact historical origin is not ancient Chinese, but the component choice is transparent.
The top 少 means 'few' or 'little', and the bottom 毛 means 'hair'. Imagine making something have fewer hairs by plucking them out one by one.
For むし, picture a person plucking hairs while ignoring the bugs (虫, むし) buzzing around: 虫 -> むし, and the plucking continues despite the insects.
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