Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
walk-up is a noun and adjective meaning "an apartment in a building without an elevator". It carries 3 recorded senses.
an apartment in a building without an elevator
an apartment building without an elevator
Definitions, synonyms and semantic relations for walk-up come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.