A genus of freshwater leeches, or a leech of this type.
From Greek klepsíne (leech), derived from kleptein (to steal), because leeches stealthily steal blood from their hosts. The genus name preserves this ancient Greek observation of leech behavior.
The Greeks named leeches 'thieves' because of their sneaky blood-stealing behavior—they invented a whole category name based on how something acts, which shows ancient people were keen observers of nature.
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