WordNet (r) 3.0 (2006):

stinking weed
    n 1: very leafy malodorous tropical weedy shrub whose seeds have
         been used as an adulterant for coffee; sometimes classified
         in genus Cassia [syn: coffee senna, mogdad coffee,
         styptic weed, stinking weed, Senna occidentalis,
         Cassia occidentalis]