sphingomyelinase
noun
sphin·go·my·elin·ase
| \ -ˈmī-ə-lə-ˌnās, -ˌnāz
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Medical Definition of sphingomyelinase
: any of several enzymes that catalyze the hydrolysis of sphingomyelin and are lacking in some metabolic deficiency diseases (as Niemann-Pick disease) in which sphingomyelin accumulates in bodily organs (as the spleen and liver)