What is the meaning of bitter?

noun

• English term for a dry sharp-tasting ale with strong flavor of hops (usually on draft. )
• The taste experience when quinine or coffee is taken into the mouth.
  • synonyms: bitterness
• The property of having a harsh unpleasant taste.
  • synonyms: bitterness

verb

• Make bitter.

adjective

• Marked by strong resentment or cynicism.
  • usage: "an acrimonious dispute"; "bitter about the divorce"
  • synonyms: acrimonious
• Very difficult to accept or bear.
  • usage: "the bitter truth"; "a bitter sorrow"
• Harsh or corrosive in tone.
  • usage: "an acerbic tone piercing otherwise flowery prose"; "a barrage of acid comments"; "her acrid remarks make her many enemies"; "bitter words"; "blistering criticism"; "caustic jokes about political assassination, talk-show hosts and medical ethics"; "a sulfurous denunciation"; "a vitriolic critique"
  • synonyms: acerb, acerbic, acid, acrid, blistering, caustic, sulfurous, sulphurous, virulent, vitriolic
• Expressive of severe grief or regret.
  • usage: "shed bitter tears"
• Proceeding from or exhibiting great hostility or animosity.
  • usage: "a bitter struggle"; "bitter enemies"
• (adj.) ()
• Causing a sharply painful or stinging sensation; used especially of cold.
  • usage: "bitter cold"; "a biting wind"
  • synonyms: biting

adverb

• Extremely and sharply.
  • usage: "it was bitterly cold"; "bitter cold"
  • synonyms: piercingly, bitterly, bitingly