Rare on its own in modern Chinese, surviving in literary words like 倏忽 (in an instant) and 倏地 (suddenly). It originally pictured a dog darting off — the dog 犬 under phonetic 攸.
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Literary only; appears in formal or classical writing, not in everyday speech.
The dog tucked at the lower right. It supplies the original image — a dog suddenly bolting away — which gave the word its sense of abrupt, flashing speed.