The Collaborative International Dictionary of English v.0.48:

Broach \Broach\, v. t. [imp. & p. p. Broached; p. pr. & vb. n.
   Broaching.] [F. brocher, fr. broche. See Broach, n.]
   1. To spit; to pierce as with a spit.
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            I'll broach the tadpole on my rapier's point.
                                                  --Shak.
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   2. To tap; to pierce, as a cask, in order to draw the liquor.
      Hence: To let out; to shed, as blood.
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            Whereat with blade, with bloody blameful blade,
            He bravely broached his boiling bloody breast.
                                                  --Shak.
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   3. To open for the first time, as stores.
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            You shall want neither weapons, victuals, nor aid; I
            will open the old armories, I will broach my store,
            and will bring forth my stores.       --Knolles.
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   4. To make public; to utter; to publish first; to put forth;
      to introduce as a topic of conversation.
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            Those very opinions themselves had broached.
                                                  --Swift.
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   5. To cause to begin or break out. [Obs.] --Shak.
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   6. (Masonry) To shape roughly, as a block of stone, by
      chiseling with a coarse tool. [Scot. & North of Eng.]
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   7. To enlarge or dress (a hole), by using a broach.
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   To broach to (Naut.), to incline suddenly to windward, so
      as to lay the sails aback, and expose the vessel to the
      danger of oversetting.
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The Collaborative International Dictionary of English v.0.48:

Broach \Broach\, n. [OE. broche, F. broche, fr. LL. brocca;
   prob. of Celtic origin; cf. W. proc thrust, stab, Gael. brog
   awl. Cf. Brooch.]
   1. A spit. [Obs.]
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            He turned a broach that had worn a crown. --Bacon.
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   2. An awl; a bodkin; also, a wooden rod or pin, sharpened at
      each end, used by thatchers. [Prov. Eng.] --Forby.
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   3. (Mech.)
      (a) A tool of steel, generally tapering, and of a
          polygonal form, with from four to eight cutting edges,
          for smoothing or enlarging holes in metal; sometimes
          made smooth or without edges, as for burnishing pivot
          holes in watches; a reamer. The broach for gun barrels
          is commonly square and without taper.
      (b) A straight tool with file teeth, made of steel, to be
          pressed through irregular holes in metal that cannot
          be dressed by revolving tools; a drift.
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   4. (Masonry) A broad chisel for stonecutting.
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   5. (Arch.) A spire rising from a tower. [Local, Eng.]
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   6. A clasp for fastening a garment. See Brooch.
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   7. A spitlike start, on the head of a young stag.
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   8. The stick from which candle wicks are suspended for
      dipping. --Knight.
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   9. The pin in a lock which enters the barrel of the key.
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WordNet (r) 3.0 (2006):

broach
    n 1: a decorative pin worn by women [syn: brooch, broach,
         breastpin]
    v 1: bring up a topic for discussion [syn: broach, initiate]

Moby Thesaurus II by Grady Ward, 1.0:

168 Moby Thesaurus words for "broach":
   advance, air, auger, bite, bleed, blue, bore, bring before,
   bring forward, bring in, bring up, chink, christen, cleave, clip,
   commend to attention, countersink, crack, crevasse, cut, cut open,
   decant, dispart, display, divaricate, divide, divulge, draft,
   draft off, drain, draw, draw from, draw off, drill, empierce,
   empty, establish, exhaust, expansive, extended, fissure, fix,
   float, fly open, found, give out, gore, gouge, gouge out, hint at,
   hole, honeycomb, impale, inaugurate, incise, induct, initiate,
   install, institute, interject, interpose, introduce, lance, launch,
   lay before, lay open, let, let blood, let out, lift up,
   make a motion, make known, make public, mention, milk, moot, move,
   needle, off-color, offer a resolution, ope, open, open up, part,
   penetrate, perforate, phlebotomize, pierce, pin, pink, pipette,
   pose, postulate, prefer, prick, propose, proposition, propound,
   pump, pump out, punch, puncture, purple, put forth, put forward,
   put it to, put out, racy, raise, ream, ream out, recommend, rent,
   riddle, rift, ring in, rip, risque, rive, run through, salty,
   scopic, separate, set agoing, set before, set forth, set on foot,
   set up, shady, siphon off, skewer, slit, spear, spicy, spike, spit,
   split, spread, spread out, spring open, stab, start, start going,
   start up, stick, submit, suck, suck out, suggest, suggestive,
   swing open, talk about, tap, tear, tear open, throw open, touch on,
   touch upon, transfix, transpierce, trepan, trephine, turn on,
   usher in, venesect, ventilate, wicked, wide