Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
small-arm is a noun meaning "a portable gun". It carries one recorded sense.
a portable gun
“he wore his firearm in a shoulder holster”
Definitions, synonyms and semantic relations for small-arm come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.