Uredo \U*re"do\, n. [L., a blast, blight, a burning itch, fr. urere to burn, to scorch.]

1. (Bot.) One of the stages in the life history of certain rusts (Uredinales), regarded at one time as a distinct genus. It is a summer stage preceding the teleutospore, or winter stage. See Uredinales, in the Supplement.

2. (Med.) Nettle rash. See Urticaria.

Source: Webster's Revised Unabridged Dictionary (1913)