1. A smut fungus of the genus Ustilago causing a smut disease of grains in which the entire head is transformed into a dusty mass of spores
   "The farmer's wheat crop was devastated by loose smut"
    
2. Disease of grains; the entire head is a dusty mass of spores
   "The wheat farmer's yield was reduced due to an outbreak of loose smut"

Derived forms: loose smuts

Type of: smut, smut fungus

Part of: genus Ustilago, Ustilago

Encyclopedia: Loose smut