Urocystis cepulae is a name commonly used for onion smut, a fungal disease that affects onion crops. Some synonyms for this disease include Allium smut, onion bunt, and onion rust. Other terms used to describe symptoms of onion smut include stunting, yellowing, and distorted growth of onion plants. The disease is caused by fungal spores that infect onion plants through their roots or leaves, often resulting in significant yield loss. Effective prevention and control measures for onion smut include crop rotation, proper sanitation, and the use of disease-resistant onion cultivars.