3. (adj)bitterness, bitter the property of having a harsh unpleasant taste
4. (adj)acrimonious, bitter marked by strong resentment or cynicism "an acrimonious dispute"; "bitter about the divorce"
5. (adj)bitter very difficult to accept or bear "the bitter truth"; "a bitter sorrow"
6. (adj)acerb, acerbic, acid, acrid, bitter, blistering, caustic, sulfurous, sulphurous, virulent, vitriolic 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"; "a vitriolic critique"
7. (adj)bitter expressive of severe grief or regret "shed bitter tears"
1. (adjective)bitter tasting strong and unpleasant bitter coffee
2. bitter feeling angry at unfair treatment; = resentful bitter about his marriage breaking up
3. bitter involving strong anger a bitter feud
4. bitter (of weather) extremely cold bitter winter air; her bitterness over the loss of her job; the bitterness of the argument; the bitterness of the chocolate; a bitterness in the air
Definition of 'bitter'
Webster Dictionary
1. (noun)bitter aA turn of the cable which is round the bitts
2. (noun)bitter any substance that is bitter. See Bitters
3. (verb)bitter having a peculiar, acrid, biting taste, like that of wormwood or an infusion of hops; as, a bitter medicine; bitter as aloes
4. (verb)bitter causing pain or smart; piercing; painful; sharp; severe; as, a bitter cold day
5. (verb)bitter causing, or fitted to cause, pain or distress to the mind; calamitous; poignant
6. (verb)bitter characterized by sharpness, severity, or cruelty; harsh; stern; virulent; as, bitterreproach
Definitions of bitter 
Afrikaans: bitter
Arabic: مُـر
Bulgarian: горчив
Brazilian: amargo
Czech: kyselý, hořký
German: bitter
Danish: bitter
Greek: πικρός
Spanish: amargo
Estonian: kibe
Farsi: تلخ؛ تند و تیز
Finnish: kitkerä
French: amer; acide
Hebrew: מָר
Hindi: कड़ुवा
Croatian: gorak
Hungarian: keserű
Indonesian: pahit
Icelandic: bitur, beiskur
Italian: amaro; aspro
Japanese: 苦い
Korean: 쓴
Lithuanian: kartus, rūgštus
Latvian: rūgts
Malay: pahit
Dutch: bitter, zuur
Norwegian: bitter, besk
Polish: gorzki
Persian: تلخ؛ تند و تیز
Pashto: تريخ (خوند) ترخه (خاطره)،
Portuguese: amargo
Romanian: amar; acid
Russian: горький
Slovak: horký, trpký
Slovenian: trpek
Serbian: gorak
Swedish: bitter, besk
Thai: ขม
Turkish: keskin, acı, buruk
Taiwanese: 有苦味的
Ukrainian: гіркий
Urdu: کڑوا ، کسیلا
Vietnamese: đắng
Chinese: 有苦味的
