The Collaborative International Dictionary of English v.0.48:

Invective \In*vec"tive\, a. [L. invectivus: cf. F. invectif. See
   Inveigh.]
   Characterized by invection; critical; denunciatory;
   satirical; abusive; railing.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Invective \In*vec"tive\, n. [F. invective.]
   An expression which inveighs or rails against a person; a
   severe or violent censure or reproach; something uttered or
   written, intended to cast opprobrium, censure, or reproach on
   another; a harsh or reproachful accusation; -- followed by
   against, having reference to the person or thing affected;
   as, an invective against tyranny.
   [1913 Webster]

         The world will be able to judge of his [Junius']
         motives for writing such famous invectives. --Sir W.
                                                  Draper.

   Syn: Abuse; censure; reproach; satire; sarcasm; railing;
        diatribe. See Abuse.
        [1913 Webster]

WordNet (r) 3.0 (2006):

invective
    n 1: abusive or venomous language used to express blame or
         censure or bitter deep-seated ill will [syn:
         vituperation, invective, vitriol]

Moby Thesaurus II by Grady Ward, 1.0:

105 Moby Thesaurus words for "invective":
   abuse, abusive, address, after-dinner speech, allocution,
   assailing, assault, attack, berating, billingsgate, bitter words,
   blackening, blameful, calumny, causticity, censorious, chalk talk,
   condemnatory, contemptuous, contumelious, contumely, cynicism,
   damnatory, debate, declamation, denunciatory, deprecative,
   deprecatory, depreciative, derisive, diatribe, disparaging, eulogy,
   execrating, execration, execrative, execratory, exhortation,
   filibuster, forensic, forensic address, formal speech,
   funeral oration, harangue, hard words, hortatory address,
   inaugural, inaugural address, innuendo, inveighing, irony, jawing,
   jeremiad, judgmental, objurgatory, obloquy, onslaught, opprobrious,
   opprobrium, oration, pep talk, peroration, philippic, pitch,
   prepared speech, prepared text, priggish, public speech, rating,
   reading, recital, recitation, reproachful, reprobative, revilement,
   reviling, ridiculing, sales talk, salutatory, salutatory address,
   sarcasm, satire, satiric wit, say, scoffing, screed, scurrile,
   scurrility, scurrilous, set speech, speech, speechification,
   speeching, talk, talkathon, tirade, tongue-lashing, truculent,
   valediction, valedictory, valedictory address, vilification,
   vilifying, vituperation, vituperative