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Medical Dictionary

adder

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noun ad·der \ˈad-ər\

Medical Definition of adder

  1. 1:  the common venomous European viper of the genus Vipera (V. berus); broadly :  a terrestrial viper of the family Viperidae

  2. 2:  any of several North American snakes (as the hognose snakes) that are harmless but are popularly believed to be venomous



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