1.Definition: causing a sharp and acrid taste experience

"Quinine is bitter"

2.Definition: causing a sharply painful or stinging sensation; used especially of cold

"Bitter cold"

Related Adjective(s):biting

3.Definition: expressive of severe grief or regret

"Shed bitter tears"

4.Definition: harsh or corrosive in tone

"Bitter words"

Related Adjective(s):acerb, acerbic, acid, acrid, blistering, caustic, sulfurous, sulphurous, virulent, vitriolic

5.Definition: marked by strong resentment or cynicism

"Bitter about the divorce"

Related Adjective(s):acrimonious

6.Definition: proceeding from or exhibiting great hostility or animosity

"A bitter struggle", "Bitter enemies"

7.Definition: very difficult to accept or bear

"The bitter truth", "A bitter sorrow"