From The Collaborative International Dictionary of English v.0.48 :
Kat \Kat\ (k[aum]t), n. (Bot.) An Arabian shrub ({Catha edulis) the leaves of which are used as tea by the Arabs. [1913 Webster]From WordNet (r) 3.0 (2006) :
kat n 1: the leaves of the shrub Catha edulis which are chewed like tobacco or used to make tea; has the effect of a euphoric stimulant; "in Yemen kat is used daily by 85% of adults" [syn: kat, khat, qat, quat, cat, Arabian tea, African tea]