Bot. a pustule, often found on the epidermis of grasses, formed by a rust fungus and consisting of uredospores
Origin of urediniumModern Latin from Classical Latin uredo (gen. uredinis), blight: see uredo and -ium
nounpl. u·re·din·i·a, also u·re·di·a
A reddish pustulelike structure that is formed in the tissue of a plant infected by a rust fungus and produces urediniospores.
Origin of urediniumNew Latin ūrēdinium from Latin ūrēdō ūrēdin- blight from ūrere to burn