Definition of adder
(Entry 1 of 2)
1
: the common venomous viper (Vipera berus) of Europe
broadly
: any of various snakes of the viper family — compare puff adder
2
: any of several North American snakes (such as the hognose snakes) that are harmless but are popularly believed to be venomous
adder
noun (2)Definition of adder (Entry 2 of 2)
: one that adds
especially
: a device (as in a computer) that performs addition
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Time Traveler for adder
The first known use of adder was in the 14th century
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