small·pox 
(smôl
p
ŏks
′)
n. An acute, highly infectious, often fatal disease caused by a poxvirus and characterized by high fever and aches with subsequent widespread eruption of pimples that blister, produce pus, and form pockmarks. Smallpox was eradicated worldwide by 1979 as a result of numerous vaccination campaigns and exists only as a laboratory specimen. Also called variola.
[Early Modern English small pockes, small pustules (as opposed to great pockes, the great pox or syphilis), from pockes, pl. of pock; see POCK.]