Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
triple-decker is a noun meaning "made with three slices of usually toasted bread". It carries one recorded sense.
made with three slices of usually toasted bread
Definitions, synonyms and semantic relations for triple-decker come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.