say it: mal-FUHNGK-shuh-ning
malfunctioning is an adjective meaning "not performing or able to perform its regular function". It carries one recorded sense.
not performing or able to perform its regular function
“a malfunctioning valve”
Definitions, synonyms and semantic relations for malfunctioning come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.