The Collaborative International Dictionary of English v.0.48:

Battery \Bat"ter*y\, n.; pl. Batteries. [F. batterie, fr.
   battre. See Batter, v. t.]
   1. The act of battering or beating.
      [1913 Webster]

   2. (Law) The unlawful beating of another. It includes every
      willful, angry and violent, or negligent touching of
      another's person or clothes, or anything attached to his
      person or held by him.
      [1913 Webster]

   3. (Mil.)
      (a) Any place where cannon or mortars are mounted, for
          attack or defense.
      (b) Two or more pieces of artillery in the field.
      (c) A company or division of artillery, including the
          gunners, guns, horses, and all equipments. In the
          United States, a battery of flying artillery consists
          usually of six guns.
          [1913 Webster]

   Barbette battery. See Barbette.

   Battery d'enfilade, or Enfilading battery, one that
      sweeps the whole length of a line of troops or part of a
      work.

   Battery en ['e]charpe, one that plays obliquely.

   Battery gun, a gun capable of firing a number of shots
      simultaneously or successively without stopping to load.


   Battery wagon, a wagon employed to transport the tools and
      materials for repair of the carriages, etc., of the
      battery.

   In battery, projecting, as a gun, into an embrasure or over
      a parapet in readiness for firing.

   Masked battery, a battery artificially concealed until
      required to open upon the enemy.

   Out of battery, or From battery, withdrawn, as a gun, to
      a position for loading.
      [1913 Webster]

   4. (Elec.)
      (a) A number of coated jars (Leyden jars) so connected
          that they may be charged and discharged
          simultaneously.
      (b) An apparatus for generating voltaic electricity.
          [1913 Webster]

   Note: In the trough battery, copper and zinc plates,
         connected in pairs, divide the trough into cells, which
         are filled with an acid or oxidizing liquid; the effect
         is exhibited when wires connected with the two
         end-plates are brought together. In Daniell's
         battery, the metals are zinc and copper, the former in
         dilute sulphuric acid, or a solution of sulphate of
         zinc, the latter in a saturated solution of sulphate of
         copper. A modification of this is the common gravity
         battery, so called from the automatic action of the
         two fluids, which are separated by their specific
         gravities. In Grove's battery, platinum is the metal
         used with zinc; two fluids are used, one of them in a
         porous cell surrounded by the other. In Bunsen's or
         the carbon battery, the carbon of gas coke is
         substituted for the platinum of Grove's. In
         Leclanch['e]'s battery, the elements are zinc in a
         solution of ammonium chloride, and gas carbon
         surrounded with manganese dioxide in a porous cell. A
         secondary battery is a battery which usually has the
         two plates of the same kind, generally of lead, in
         dilute sulphuric acid, and which, when traversed by an
         electric current, becomes charged, and is then capable
         of giving a current of itself for a time, owing to
         chemical changes produced by the charging current. A
         storage battery is a kind of secondary battery used
         for accumulating and storing the energy of electrical
         charges or currents, usually by means of chemical work
         done by them; an accumulator.
         [1913 Webster]

   5. A number of similar machines or devices in position; an
      apparatus consisting of a set of similar parts; as, a
      battery of boilers, of retorts, condensers, etc.
      [1913 Webster]

   6. (Metallurgy) A series of stamps operated by one motive
      power, for crushing ores containing the precious metals.
      --Knight.
      [1913 Webster]

   7. The box in which the stamps for crushing ore play up and
      down.
      [1913 Webster]

   8. (Baseball) The pitcher and catcher together.
      [1913 Webster]

WordNet (r) 3.0 (2006):

battery
    n 1: group of guns or missile launchers operated together at one
         place
    2: a device that produces electricity; may have several primary
       or secondary cells arranged in parallel or series [syn:
       battery, electric battery]
    3: a collection of related things intended for use together;
       "took a battery of achievement tests"
    4: a unit composed of the pitcher and catcher
    5: a series of stamps operated in one mortar for crushing ores
       [syn: battery, stamp battery]
    6: the heavy fire of artillery to saturate an area rather than
       hit a specific target; "they laid down a barrage in front of
       the advancing troops"; "the shelling went on for hours
       without pausing" [syn: barrage, barrage fire, battery,
       bombardment, shelling]
    7: an assault in which the assailant makes physical contact
       [syn: battery, assault and battery]

Moby Thesaurus II by Grady Ward, 1.0:

185 Moby Thesaurus words for "battery":
   KP, Leyden jar, accumulator, amateur athlete, archer, army,
   army group, array, artillery, athlete, atomic battery, ballplayer,
   baseballer, baseman, bastinado, basting, batch, battalion, batter,
   battle group, beating, bells, belting, block, blocking back, body,
   bones, bowman, brigade, buffeting, bunch, bundle, cadre, caning,
   cannon, cannonry, castanets, catcher, celesta, cell, center, chime,
   chimes, clappers, clot, clubbing, clump, cluster, coach,
   coast artillery, cohort, column, combat command, combat team,
   company, competitor, corporal punishment, corps, cowhiding,
   crash cymbal, cricketer, cudgeling, cymbals, defensive lineman,
   detachment, detail, division, drubbing, dry cell,
   electronic battery, end, field army, field artillery, field train,
   file, finger cymbals, flagellation, flailing, flak, flogging,
   flying column, footballer, fuel cell, fustigation, gamelan,
   games-player, gamester, garrison, glockenspiel, gong, guard,
   handbells, heavy field artillery, horsewhipping, idiophone,
   infielder, jock, jumper, kit, kitchen police, lacing, lashing,
   legion, lineman, lot, lyra, maniple, maraca, marimba, metallophone,
   offensive lineman, orchestral bells, ordnance, organization,
   outfield, outfielder, outfit, pack, percussion,
   percussion instrument, percussions, percussive, phalanx,
   pistol-whipping, platoon, player, poloist, posse,
   professional athlete, pugilist, quarterback, racer, rank, rattle,
   rattlebones, rawhiding, regiment, scourging, section, series, set,
   siege artillery, siege engine, sizzler, skater, snappers,
   solar battery, spanking, sport, sportsman, squad, squadron,
   storage battery, storage cell, strapping, stripes, suit, suite,
   swingeing, switching, tackle, tactical unit, tailback, tam-tam,
   task force, thrashing, tintinnabula, tonitruone, toxophilite,
   train, trench artillery, triangle, troop, trouncing, truncheoning,
   tubular bells, unit, vibes, vibraphone, wet cell, whipping, wing,
   wingback, wrestler, xylophone



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

BATTERY. It is proposed to consider, 1. What is a battery; 2. When a
battery, may be justified.
     2. - 1. A battery is the unlawful touching the person of another by the
aggressor himself, or any other substance put in motion by him. 1 Saund. 29,
b. n. 1; Id. 13 & 14, n. 3. It must be either willfully committed, or proceed
from want of due care. Str. 596; Hob. 134; Plowd. 19 3 Wend. 391. Hence an
injury, be it never so small, done to the person of another, in an angry,
spiteful, rude or insolent manner, as by spitting in his face, or any way
touching him in anger, or violently jostling him, are batteries in the eye
of the law. 1 Hawk. P. C. 263. See 1 Selw. N. P. 33, 4. And any thing
attached to the person partakes of its inviolability if, therefore, A
strikes a cane in the hands of B, it is a battery. 1 Dall. 1 14 1 Ch. Pr.
37; 1 Penn. R. 380; 1 Hill's R. 46; 4 Wash. C. C. R. 534 . 1 Baldw. R. 600.
     3. - 2. A battery may be justified, 1. on the ground of the parental
relation 2. in the exercise of an office; 3. under process of a court of
justice or other legal tribunal 4. in aid of an authority in law; and
lastly, as a necessary means of defence.
     4. First. As a salutary mode of correction. For example: a parent may
correct his child, a master his apprentice, a schoolmaster his scholar; 24
Edw. IV.; Easter, 17, p. 6 and a superior officer, one under his command.
Keilw. pl. 120, p. 136 Bull. N. P. 19 Bee, 161; 1 Bay, 3; 14 John. R. 119 15
Mass. 365; and vide Cowp. 173; 15 Mass. 347.
     5. - 2. As a means to preserve the peace; and therefore if the
plaintiff assaults or is fighting with another, the defendant may lay hands
upon him, and restrain him until his anger is cooled; but he cannot strike
him in order to protect 'the party assailed, as he way in self-defence. 2
Roll. Abr. 359, E, pl. 3.
     6. - 3. Watchmen may arrest, and detain in prison for examination,
persons walking in the streets by might, whom there is reasonable ground to
suspect of felony, although there is no proof of a felony having been
committed. 3 Taunt. 14.
     7. - 4. Any person has a right to arrest another to prevent a felony.
     8. - 5. Any one may arrest another upon suspicion of felony, provided a
felony has actually been committed and there is reasonable ground for
suspecting the person arrested to be the criminal, and that the party making
the arrest, himself entertained the suspicion.
     9. - 6. Any private individual may arrest a felon. Hale's P. C. 89.
    10. - 7. It is lawful for every man to lay hands on another to preserve
public decorum; as to turn him out of church, and to prevent him from
disturbing the congregation or a funeral ceremony. 1 Mod. 168; and see 1
Lev. 196; 2 Keb. 124. But a request to desist should be first made, unless
the urgent necessity of the case dispenses with it.
    11. Secondly. A battery may be justified in the exercise of an office.
1. A constable may freshly arrest one who, in, his view, has committed a
breach of the peace, and carry him before a magistrate. But if an offence
has been committed out of the constable's sight, he cannot arrest, unless it
amounts to a felony; 1 Brownl. 198 or a felony is likely to ensue. Cro.
Eliz. 375.
    12. - 2. A justice of the peace may generally do all acts which a
constable has authority to perform hence he may freshly arrest one who, in
his view has broken the peace; or he may order a constable at the moment to
take him up. Kielw. 41.
    13. Thirdly. A battery may be justified under the process of a court of
justice, or of a magistrate having competent jurisdiction. See 16 Mass. 450;
13 Mass. 342.
    14. Fourthly. A battery may be justified in aid of an authority in law.
Every person is empowered to restrain breaches of the peace, by virtue of
the authority vested in him by the law.
    15. Lastly. A battery may be justified as a necessary means of defence.
1. Against the plaintiffs assaults in the following instances: In defence of
himself, his wife, 3 Salk. 46, his child, and his servant. Ow. 150; sed vide
1 Salk. 407. So, likewise, the wife may justify a battery in defending her
husband; Ld. Raym. 62; the child its parent; 3 Salk. 46; and the servant his
master. In these situations, the party need not wait until a blow has been
given, for then he might come too late, and be disabled from warding off a
second stroke, or from protecting the person assailed. Care, however, must
be taken, that the battery do not exceed the bounds of necessary defence and
protection; for it is only permitted as a means to avert an impending evil,
which might otherwise overwhelm the party, and not as a punishment or
retaliation for the injurious attempt. Str. 953. The degree of force
necessary to repel an assault will naturally depend upon, and be
proportioned to, the violence of the assailant; but with this limitation any
degree is justifiable. Ld. Raym. 177; 2 Salk. 642.
    16. - 2. A battery may likewise be justified in the necessary defence of
one's property; if the plaintiff is in the act of entering peaceably upon
the defendant's land, or having entered, is discovered, not committing
violence, a request to depart is necessary in the first instance; 2 Salk.
641; and if the plaintiff refuses, the defendant may then, and not till
then, gently lay hands upon the plaintiff to remove him from the close and
for this purpose may use, if necessary, any degree of force short of
striking the plaintiff, as by thrusting him off. Skinn. 228. If the
plaintiff resists, the defendant may oppose force to force. 8 T. R. 78. But
if the plaintiff is in the act of forcibly entering upon the land, or having
entered, is discovered subverting the soil, cutting down a tree or the like,
2 Salk. 641, a previous request is unnecessary, and the defendant may
immediately lay hands upon the plaintiff. 8 T. R. 78. A man may justify a
battery in defence of his personal property, without a previous request, if
another forcibly attempt to take away such property. 2 Salk. 641. Vide
Rudeness; Wantonness.