[syn: acerb, acerbic, acid, acrid, bitter, blistering, caustic, sulfurous, sulphurous, virulent, vitriolic]
The Collaborative International Dictionary of English v.0.48:
Acerb \A*cerb"\, a. [L. acerbus, fr. acer sharp: cf. F. acerbe.
   See Acrid.]
   Sour, bitter, and harsh to the taste, as unripe fruit; sharp
   and harsh.
   [1913 Webster]
WordNet (r) 3.0 (2006):
acerb
    adj 1: sour or bitter in taste [syn: acerb, acerbic,
           astringent]
    2: 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" [syn:
       acerb, acerbic, acid, acrid, bitter, blistering,
       caustic, sulfurous, sulphurous, virulent,
       vitriolic]