Dobson

wiktionary

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From a medieval diminutive form of the given name Robert +‎ -son.

etymonline

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dobson (n.)

name for the predatory larva of a type of large insect of eastern North America, by 1870, of uncertain origin, originally a term among fishermen, who use it for bait. The adult male form is large and ferocious-looking but harmless to humans. It has been called dobson fly since at least 1906; the earlier name was hellgrammite (by 2868).