1 an evergreen tree, Quassia amara, native to S. America.
2 the wood, bark, or root of this tree, yielding a bitter medicinal tonic and insecticide.
G. Quassi, 18th-c. Surinam slave, who discovered its medicinal properties
unsavoriness, amaritude, acrimony, acridity (bitterness), roughness, acerbity, austerity, gall and wormwood, rue, quassia
, aloes, marah, sickener, unsavory, unpalatable, unsweetened, unsweet, ill-flavored, bitter, bitter as gall, acrid, acrimonious, rough, offensive, repulsive, nasty, sickening, nauseous, loathsome, fulsome, unpleasant.