surname, talk too much, verbose
詹 centers on excessive or flowing speech: talking too much, being verbose. The surname sense is a separate application of the character as a name.
詹 is composed of 厃 (a person leaning over a cliff) and 言 (speech), suggesting words pouring out or excessive talking. The exact historical development is uncertain, but the component combination fits the meaning of verbosity.
The top 厃 looks like a person leaning over a cliff, and below is 言 (speech). Imagine someone leaning over a cliff and talking nonstop, their words flowing endlessly like a verbose speech.
For セン, picture a verbose person sending (send -> セン) a flood of words over the cliff. The 'send' sound cues セン while the scene matches the talkative meaning.
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