1. [n]  the property of having a harsh unpleasant taste
2. [n]  the taste experience when quinine or coffee is taken into the mouth
3. [n]  (British) dry sharp-tasting ale with strong flavor of hops
4. [adv]  extremely and sharply; "it was bitterly cold"; "bitter cold"
5. [adj]  marked by strong resentment or cynicism; "an acrimonious dispute"; "bitter about the divorce"
6. [adj]  proceeding from or exhibiting great hostility or animosity; "a bitter struggle"; "bitter enemies"
7. [adj]  expressive of severe grief or regret; "shed bitter tears"
8. [adj]  causing a sharply painful or stinging sensation; used especially of cold; "bitter cold"; "a biting wind"
9. [adj]  harsh or corrosive in tone; "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"
10. [adj]  one of the four basic taste sensations; sharp and disagreeable; like the taste of quinine
11. [adj]  very difficult to accept or bear; "the bitter truth"; "a bitter sorrow"
12. [v]  make bitter

Bitter
Bitter

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1. \Bit"ter\, n. [See {Bitts}.] (Naut.)
   AA turn of the cable which is round the bitts.
   {Bitter end}, that part of a cable which is abaft the bitts,
      and so within board, when the ship rides at anchor.
   

2. \Bit"ter\, a. [AS. biter; akin to Goth. baitrs, Icel.
   bitr, Dan., Sw., D., & G. bitter, OS. bittar, fr. root of E.
   bite. See {Bite}, v. t.]
   1. Having a peculiar, acrid, biting taste, like that of
      wormwood or an infusion of hops; as, a bitter medicine;
      bitter as aloes.
   2. Causing pain or smart; piercing; painful; sharp; severe;
      as, a bitter cold day.
   3. Causing, or fitted to cause, pain or distress to the mind;
      calamitous; poignant.
            It is an evil thing and bitter, that thou hast
            forsaken the Lord thy God.            --Jer. ii. 19.
   4. Characterized by sharpness, severity, or cruelty; harsh;
      stern; virulent; as, bitter reproach.
            Husbands, love your wives, and be not bitter against
            them.                                 --Col. iii.
                                                  19.
   5. Mournful; sad; distressing; painful; pitiable.
            The Egyptians . . . made their lives bitter with
            hard bondage.                         --Ex. i. 14.
   {Bitter apple}, {Bitter cucumber}, {Bitter gourd}. (Bot.) See
      {Colocynth}.
   {Bitter cress} (Bot.), a plant of the genus {Cardamine}, esp.
      {C. amara}.
   {Bitter earth} (Min.), tale earth; calcined magnesia.
   {Bitter principles} (Chem.), a class of substances, extracted
      from vegetable products, having strong bitter taste but
      with no sharply defined chemical characteristics.
   {Bitter salt}, Epsom salts; magnesium sulphate.
   {Bitter vetch} (Bot.), a name given to two European
      leguminous herbs, {Vicia Orobus} and {Ervum Ervilia}.
   {To the bitter end}, to the last extremity, however
      calamitous.
   Syn: Acrid; sharp; harsh; pungent; stinging; cutting; severe;
        acrimonious.
   

3. \Bit"ter\, n.
   Any substance that is bitter. See {Bitters}.
   

4. \Bit"ter\, v. t.
   To make bitter. --Wolcott.
   

Bitterness is symbolical of affliction, misery, and servitude (Ex. 1:14; Ruth 1:20; Jer. 9:15). The Chaldeans are called the "bitter and hasty nation" (Hab. 1:6). The "gall of bitterness" expresses a state of great wickedness (Acts 8:23). A "root of bitterness" is a wicked person or a dangerous sin (Heb. 12:15).

The Passover was to be eaten with "bitter herbs" (Ex. 12:8; Num. 9:11). The kind of herbs so designated is not known. Probably they were any bitter herbs obtainable at the place and time when the Passover was celebrated. They represented the severity of the servitude under which the people groaned; and have been regarded also as typical of the sufferings of Christ.