neuraminidase Syllabification: (neu·ra·min·i·dase)Pronunciation: /ˌn(y)o͝orəˈminəˌdās/Definition of neuraminidase noun Biochemistry an enzyme, present in many pathogenic or symbiotic microorganisms, that catalyzes the breakdown of glycosides containing neuraminic acid. neuraminidase in other Oxford dictionaries Definition of neuraminidase in the British & World English dictionary