Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
membrane-forming is an adjective meaning "characterized by formation of a membrane (or something resembling a membrane)". It carries one recorded sense.
characterized by formation of a membrane (or something resembling a membrane)
“membranous gastritis”
Definitions, synonyms and semantic relations for membrane-forming come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.