arms vs hardware

arms and hardware both are nouns.

Word	Noun	Adjective	Verb	Adverb
arms	Yes	No	No	No
hardware	Yes	No	No	No

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

arms (noun)	hardware (noun)
weapons considered collectively	(computer science) the mechanical, magnetic, electronic, and electrical components making up a computer system
the official symbols of a family, state, etc.	major items of military weaponry (as tanks or missile)
	instrumentalities (tools or implements) made of metal