From The Collaborative International Dictionary of English v.0.48 :
Souchong \Sou*chong"\, n. [Chin. seou chong little plant or
sort.]
A kind of black tea of a fine quality.
[1913 Webster]
From WordNet (r) 3.0 (2006) :
souchong
n 1: a fine quality of black tea native to China [syn:
souchong, soochong]