WordNet sense 1 (the taste experience when quinine or coffee is taken into the mouth):

bitterness

WordNet sense 2 (incapable of being put up with):

intolerable, unbearable, unendurable

WordNet sense 3 (pleasing to the sense of taste):

tasty

WordNet sense 4 (harsh or corrosive in tone):

acerbic, acid, acrid, blistering, caustic, sulfurous, venomous, virulent, vitriolic, acerb, sulphurous

WordNet sense 5 (disagreeable to the senses, to the mind, or feelings ):

unpleasant

WordNet sense 6 (causing a sharply painful or stinging sensation; used especially of cold):

biting

WordNet sense 7 (causing physical or psychological pain):

painful

WordNet sense 8 (experiencing or marked by or expressing sorrow especially that associated with irreparable loss):

sorrowful

WordNet sense 9 (extremely and sharply):

bitingly, bitterly, piercingly

WordNet sense 10 (marked by strong resentment or cynicism):

acrimonious

WordNet sense 11 (full of or marked by resentment or indignant ill will):

resentful