computer vs adder

computer and adder both are nouns.

Word	Noun	Adjective	Verb	Adverb
computer	Yes	No	No	No
adder	Yes	No	No	No

As nouns, adder is a hyponym of computer; that is, adder is a word with a more specific, narrower meaning than computer:

Other hyponyms of computer include number cruncher, actuary, statistician, subtracter.

computer (noun)	adder (noun)
a machine for performing calculations automatically	small terrestrial viper common in northern Eurasia
an expert at calculation (or at operating calculating machines)	a machine that adds numbers
	a person who adds numbers