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Webster 1913 Edition
Red-gum
Red′-gumˊ
(-g?mˊ)
, Noun.
 [OE. 
reed gounde
; AS. reád 
red + gund 
matter, pus.] 1. 
(Med.) 
An eruption of red pimples upon the face, neck, and arms, in early infancy; tooth rash; strophulus. 
Good.
 2. 
A name of rust on grain. See 
Rust
.