small arm

noun
1.
Usually, small arms. a firearm designed to be held in one or both hands while being fired: in the U.S. the term is applied to weapons of a caliber of up to one inch (2.5 cm).
Origin
1680-90
Related forms
small-armed, adjective
British Dictionary definitions for small arms

small arms

plural noun
1.
portable firearms of relatively small calibre
Encyclopedia Article for small arms

small arm

any handheld firearm.

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