Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
spot-welding is a noun meaning "creating an overlapping joint by welding at small points". It carries one recorded sense.
creating an overlapping joint by welding at small points
Definitions, synonyms and semantic relations for spot-welding come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.