hand calculator vs calculator

hand calculator and calculator both are nouns.

Word	Noun	Adjective	Verb	Adverb
hand calculator	Yes	No	No	No
calculator	Yes	No	No	No

As nouns, calculator is a hypernym of hand calculator; that is, calculator is a word with a broader meaning than hand calculator:

hand calculator: a calculator small enough to hold in the hand or carry in a pocket
calculator: a small machine that is used for mathematical calculations; can be mechanical or electronic

Other hypernyms of hand calculator include calculating machine.

hand calculator (noun)	calculator (noun)
a calculator small enough to hold in the hand or carry in a pocket	a small machine that is used for mathematical calculations; can be mechanical or electronic
	an expert at calculation (or at operating calculating machines)