calculator vs calculating machine

calculator and calculating machine both are nouns.

Word	Noun	Adjective	Verb	Adverb
calculator	Yes	No	No	No
calculating machine	Yes	No	No	No

As nouns, calculator and calculating machine are synonyms defined as:

calculator and calculating machine: a small machine that is used for mathematical calculations; can be mechanical or electronic

calculator (noun)	calculating machine (noun)
a small machine that is used for mathematical calculations; can be mechanical or electronic	a small machine that is used for mathematical calculations; can be mechanical or electronic
an expert at calculation (or at operating calculating machines)