insulin-dependent diabetes mellitus n : severe diabetes mellitus with an early onset; characterized by polyuria and excessive thirst and increased appetite and weight loss and episodic ketoacidosis; diet and insulin injections are required to control the disease [syn: {type I diabetes}, {IDDM}, {juvenile-onset diabetes}, {juvenile diabetes}, {growth-onset diabetes}, {ketosis-prone diabetes}, {ketoacidosis-prone diabetes}, {autoimmune diabetes}]