isoniazid Syllabification: (i·so·ni·a·zid)Pronunciation: /ˌīsəˈnīəzid/Definition of isoniazid noun Medicine a synthetic compound used as a bacteriostatic drug, chiefly to treat tuberculosis. A derivative of nicotinic acid and hydrazine; chemical formula: C5H5NCONHNH2 Origin: 1950s: from iso- 'equal' + ni(cotinic) + (hydr)azine + -ideisoniazid in other Oxford dictionaries Definition of isoniazid in the British & World English dictionary
