computing device vs electronic computer

computing device and electronic computer both are nouns.

Word	Noun	Adjective	Verb	Adverb
computing device	Yes	No	No	No
electronic computer	Yes	No	No	No

As nouns, computing device and electronic computer are synonyms defined as:

computing device and electronic computer: a machine for performing calculations automatically

Other synonyms of computing device include computer, computing machine, data processor, information processing system.

computing device (noun)	electronic computer (noun)
a machine for performing calculations automatically	a machine for performing calculations automatically