small-arm has definitions from the field of arms
1
[ noun ] (arms) a portable gun

Synonyms

firearm piece

Examples

"he wore his firearm in a shoulder holster"

Used in print

(Sports Age, 24:9...)

And millions of rounds of entirely new and modern small-arms ammunition , designed for today 's hunting and target shooting .

(Peter J. White, "Report on Laos"...)

Amid the crackle of small_arms and automatic weapons , I heard the thumping of mortars .

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