The Collaborative International Dictionary of English v.0.48:

Indictment \In*dict"ment\, n. [Cf. Inditement.]
   [1913 Webster]
   1. The act of indicting, or the state of being indicted.
      [1913 Webster]

   2. (Law) The formal statement of an offense, as framed by the
      prosecuting authority of the State, and found by the grand
      jury.
      [1913 Webster]

   Note: To the validity of an indictment a finding by the grand
         jury is essential, while an information rests only on
         presentation by the prosecuting authority.
         [1913 Webster]

   3. An accusation in general; a formal accusation.
      [1913 Webster]

   Bill of indictment. See under Bill.
      [1913 Webster]

WordNet (r) 3.0 (2006):

indictment
    n 1: a formal document written for a prosecuting attorney
         charging a person with some offense [syn: indictment,
         bill of indictment]
    2: an accusation of wrongdoing; "the book is an indictment of
       modern philosophy"

Moby Thesaurus II by Grady Ward, 1.0:

49 Moby Thesaurus words for "indictment":
   accusal, accusation, accusing, allegation, allegement, anathema,
   arraignment, bail, bill of particulars, blame, bringing of charges,
   bringing to book, castigation, censure, charge, complaint,
   condemnation, count, damnation, decrial, delation, denouncement,
   denunciation, excoriation, flaying, fulmination, fustigation,
   impeachment, implication, imputation, information, innuendo,
   insinuation, lawsuit, laying of charges, pillorying, plaint,
   presentment, prosecution, reprehension, reproach, reprobation,
   skinning alive, stricture, suit, taxing, true bill,
   unspoken accusation, veiled accusation



Bouvier's Law Dictionary, Revised 6th Ed (1856):

INDICTMENT, crim. law, practice. A written accusation of one or more persons
of a crime or misdemeanor, presented to, and preferred upon oath or
affirmation, by a grand jury legally convoked. 4 Bl. Com. 299; Co. Litt.
126; 2 Hale, 152; Bac. Ab. h.t.; Com. Dig. h.t. A; 1 Chit. Cr. L. 168.
     2. This word, indictment, is said to be derived from the old French
word inditer, which signifies to indicate; to show, or point out. Its object
is to indicate the offence charged against the accused. Rey, des Inst.
l'Angl. tome 2, p. 347.
     3. To render an indictment valid, there are certain essential and
formal requisites. The essential requisites are, 1st. That the indictment be
presented to some court having jurisdiction. of the offence stated therein.
2d. That it appear to have been found by the grand jury of the proper county
or district. 3d. That the indictment be found a true bill, and signed by the
foreman of the grand jury. 4th. That it be framed with sufficient certainty;
for this purpose the charge must contain a certain description of the crime
or misdemeanor, of which the defendant is accused, and a statement of the
facts by which it is constituted, so as to identify the accusation. Cowp.
682, 3; 2 Hale, 167; 1 Binn. R. 201; 3 Binn. R; 533; 1 P. A. Bro. R. 360; 6
S. & R. 398 4 Serg. & Rawle, 194; 4 Bl. Com. 301; Yeates, R. 407; 4 Cranch,
R. 167. 5th. The indictment must be in the English language. But if any
document in a foreign language, as a libel, be necessarily introduced, it
should be set out in the original tongue, and then translated, showing its
application. 6 T. R. 162.
     4. Secondly, formal requisites are, 1st. The venue, which, at common
law should always be laid in the county where the offence has been
committed, although the charge is in its nature transitory, as a battery.
Hawk. B. 2, c. 25, s. 35. The venue is stated in the margin thus, "City and
county of _____ to wit." 2d. The presentment, which must be in the present
tense, and is usually expressed by the following formula, "the grand inquest
of the commonwealth of ______ inquiring for the city and county aforesaid,
upon their oaths and affirmations present." See, as to the venue, 1 Pike, R.
171; 9 Yerg. 357. 3d. The name and addition of the defendant; but in case an
error has been made in this respect, it is cured by the plea of the
defendant. Bac. Ab. Misnomer, B; Indictment, G 2; 2 Hale, 175; 1 Chit. Pr.
202. 4th. The names of third persons, when they must be necessarily
mentioned in the indictment, should be stated with certainty to a common
intent, so as sufficiently to inform the defendant who are his accusers.
When, however, the names of third persons cannot be ascertained, it is
sufficient, in some cases, to state "a certain person or persons to the
jurors aforesaid unknown." Hawk. B. 2, c. 25, s. 71; 2 East, P. C. 651, 781;
2 Hale, 181; Plowd. 85; Dyer, 97, 286; 8 C. & P. 773. See Unknown. 5th. The
time when the offence was committed, should in general be stated to be on a
specific year and day. In some offences, as in perjury, the day must be
precisely stated; 2 Wash. C. C. Rep. 328; but although it is necessary that
a day certain should be laid in the indictment, yet, in general, the
prosecutor may give evidence of an offence committed on any other day
previous to the finding of the, indictment. 5 Serg. & Rawle, 316. Vide 11
Serg. & Rawle, 177; 1 Chit. Cr. Law, 217, 224; 1 Ch. Pl. Index, tit. Time.
See 17 Wend. 475; 2 Dev. 567; 5 How. Mis. 14; 4 Dana. 496; C. & N. 369; 1
Hawks, 460. 6th. The offence should be properly described. This is done by
stating the substantial circumstances necessary to show the nature of the
crime and, next, the formal allegations and terms of art required by law. 1.
As to the substantial circumstances. The whole of the facts of the case
necessary to make it appear judicially to the court that the indictors have
gone upon sufficient premises, should be set forth; but there should be no
unnecessary matter or any thing which on its face makes the indictment
repugnant, inconsistent, or absurd. Hale, 183; Hawk. B. 2, c. 25, s. 57; Ab.
h.t. G 1; Com. Dig. h.t. G 3; 2 Leach, 660; 2 Str. 1226. All indictments
ought to charge a man with a particular offence, and not with being an
offender in general: to this rule there are some exceptions, as indictments
against a common barrator, a common scold, and the keeper of a common bawdy
house; such persons may be indicted by these general words. 1 Chit. Cr. Law,
230, and the authorities there cited. The offence must not be stated in the
disjunctive, so as to leave it uncertain on what it is intended to rely as
an accusation; as, that the defendant erected or caused to be. erected a
nuisance. 2 Str. 900; 1 Chit. Cr. Law, 236.
     2. There are certain terms of art used, so appropriated by the law to
express the precise idea which it entertains of the offence, that no other
terms, however synonymous they may seem, are capable of filling the same
office: such, for example, as traitorously, (q.v.) in treason; feloniously,
(q.v.) in felony; burglariously, (q.v.) in burglary; maim, (q.v.) in
mayhem, &c. 7th. The conclusion of the indictment should conform to the
provision of the constitution of the state on the subject, where there is
such provision; as in Pennsylvania, Const. art. V., s. 11, which provides,
that "all prosecutions shall be carried on in the name and by the authority
of the commonwealth of Pennsylvania, and conclude against the peace and
dignity of the same." As to the necessity and propriety of having several
counts in an indictment, vide 1 Chit. Cr. Law, 248; as to. joinder of
several offences in the same indictment, vide 1 Chit. Cr. Law, 253; Arch.
Cr. Pl. 60; several defendants may in some cases be joined in the same
indictment. Id. 255; Arch. Cr. Pl. 59. When an indictment may be amended,
see Id. 297. Stark. Cr. Pl. 286; or quashed, Id. 298 Stark. Cr. Pl. 831;
Arch. Cr. 66. Vide; generally, Arch. Cr. Pl. B. 1, part 1, c. 1; p. 1 to 68;
Stark. Cr. Pl. 1 to 336; 1 Chit. Cr. Law, 168 to 304; Com. Dig. h.t.: Vin.
Ab. h.t.; Bac. Ab. h.t.; Dane's Ab. h.t.; Nels. Ab. h.t.; Burn's Just.
h.t.; Russ. on Cr. Index, h.t.,
     5. By the Constitution of the United States, Amend. art. 5, no person
shall be held to answer for a capital, or otherwise infamous crime, unless
on a presentment or indictment of a grand jury, except in cases arising in
the land or naval forces, or in the militia, when in actual service in time
of war, or public danger.