The Collaborative International Dictionary of English v.0.48:

Shaft \Shaft\, n. [OE. shaft, schaft, AS. sceaft; akin to D.
   schacht, OHG. scaft, G. schaft, Dan. & Sw. skaft handle,
   haft, Icel. skapt, and probably to L. scapus, Gr. ????, ????,
   a staff. Probably originally, a shaven or smoothed rod. Cf.
   Scape, Scepter, Shave.]
   1. The slender, smooth stem of an arrow; hence, an arrow.
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            His sleep, his meat, his drink, is him bereft,
            That lean he wax, and dry as is a shaft. --Chaucer.
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            A shaft hath three principal parts, the stele
            [stale], the feathers, and the head.  --Ascham.
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   2. The long handle of a spear or similar weapon; hence, the
      weapon itself; (Fig.) anything regarded as a shaft to be
      thrown or darted; as, shafts of light.
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            And the thunder,
            Winged with red lightning and impetuous rage,
            Perhaps hath spent his shafts.        --Milton.
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            Some kinds of literary pursuits . . . have been
            attacked with all the shafts of ridicule. --V. Knox.
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   3. That which resembles in some degree the stem or handle of
      an arrow or a spear; a long, slender part, especially when
      cylindrical. Specifically: (a) (Bot.) The trunk, stem, or
      stalk of a plant.
      (b) (Zool.) The stem or midrib of a feather. See Illust.
          of Feather.
      (c) The pole, or tongue, of a vehicle; also, a thill.
      (d) The part of a candlestick which supports its branches.
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                Thou shalt make a candlestick of pure gold . . .
                his shaft, and his branches, his bowls, his
                knops, and his flowers, shall be of the same.
                                                  --Ex. xxv. 31.
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      (e) The handle or helve of certain tools, instruments,
          etc., as a hammer, a whip, etc.
      (f) A pole, especially a Maypole. [Obs.] --Stow.
      (g) (Arch.) The body of a column; the cylindrical pillar
          between the capital and base (see Illust. of
          Column). Also, the part of a chimney above the roof.
          Also, the spire of a steeple. [Obs. or R.] --Gwilt.
      (h) A column, an obelisk, or other spire-shaped or
          columnar monument.
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                Bid time and nature gently spare
                The shaft we raise to thee.       --Emerson.
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      (i) (Weaving) A rod at the end of a heddle.
      (j) (Mach.) A solid or hollow cylinder or bar, having one
          or more journals on which it rests and revolves, and
          intended to carry one or more wheels or other
          revolving parts and to transmit power or motion; as,
          the shaft of a steam engine. See Illust. of
          Countershaft.
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   4. (Zool.) A humming bird (Thaumastura cora) having two of
      the tail feathers next to the middle ones very long in the
      male; -- called also cora humming bird.
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   5. [Cf. G. schacht.] (Mining) A well-like excavation in the
      earth, perpendicular or nearly so, made for reaching and
      raising ore, for raising water, etc.
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   6. A long passage for the admission or outlet of air; an air
      shaft.
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   7. The chamber of a blast furnace.
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   Line shaft (Mach.), a main shaft of considerable length, in
      a shop or factory, usually bearing a number of pulleys by
      which machines are driven, commonly by means of
      countershafts; -- called also line, or main line.

   Shaft alley (Naut.), a passage extending from the engine
      room to the stern, and containing the propeller shaft.

   Shaft furnace (Metal.), a furnace, in the form of a
      chimney, which is charged at the top and tapped at the
      bottom.
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WordNet (r) 3.0 (2006):

shaft
    n 1: a line that forms the length of an arrow pointer
    2: an aggressive remark directed at a person like a missile and
       intended to have a telling effect; "his parting shot was
       `drop dead'"; "she threw shafts of sarcasm"; "she takes a dig
       at me every chance she gets" [syn: shot, shaft, slam,
       dig, barb, jibe, gibe]
    3: a long rod or pole (especially the handle of an implement or
       the body of a weapon like a spear or arrow)
    4: a column of light (as from a beacon) [syn: beam, beam of
       light, light beam, ray, ray of light, shaft, shaft
       of light, irradiation]
    5: the main (mid) section of a long bone [syn: diaphysis,
       shaft]
    6: obscene terms for penis [syn: cock, prick, dick,
       shaft, pecker, peter, tool, putz]
    7: a long pointed rod used as a tool or weapon [syn: spear,
       lance, shaft]
    8: a vertical passageway through a building (as for an elevator)
    9: (architecture) upright consisting of the vertical part of a
       column [syn: shaft, scape]
    10: a long vertical passage sunk into the earth, as for a mine
        or tunnel
    11: a revolving rod that transmits power or motion [syn:
        rotating shaft, shaft]
    12: the hollow spine of a feather [syn: quill, calamus,
        shaft]
    v 1: equip with a shaft
    2: defeat someone through trickery or deceit [syn: cheat,
       chouse, shaft, screw, chicane, jockey]

Moby Thesaurus II by Grady Ward, 1.0:

209 Moby Thesaurus words for "shaft":
   abysm, abyss, adit, air duct, air hole, air passage, air shaft,
   air tube, airway, antenna tower, arch, arrow, arrowhead, baluster,
   balustrade, banister, bank, barb, barbican, barbule, barrel,
   barrow, base, beam, belfry, bell tower, blowhole, bobtailed arrow,
   bolt, boundary stone, brass, breathing hole, bust, cairn,
   campanile, caryatid, cavity, cenotaph, chasm, chested arrow,
   cilium, cloth yard shaft, coal mine, colliery, colonnade, colossus,
   column, crater, crevasse, cromlech, cross, cup, cupola, cut,
   cyclolith, dado, dart, deep, depth, derrick, die, dig, diggings,
   dolmen, dome, duct, excavation, filament, filamentule, fire tower,
   flight, flue, footstalk, footstone, gibe, gleam, gold mine, grave,
   gravestone, gulf, handle, headstone, helve, hoarstone, hole,
   hollow, inscription, jab, jack, jibe, knock, lantern, lighthouse,
   louver, louverwork, marker, martello, martello tower, mast,
   mausoleum, megalith, memento, memorial, memorial arch,
   memorial column, memorial statue, memorial stone, menhir, minaret,
   mine, monolith, monument, mound, naris, necrology, newel-post,
   nostril, obelisk, obituary, observation tower, open cut, opencast,
   pagoda, pedestal, pedicel, peduncle, pencil, pier, pilaster, pile,
   piling, pillar, pinnacle, pit, plaque, plinth, pole, post, potshot,
   prize, put-down, pylon, pyramid, quarrel, quarry, queen-post,
   quill, ray, reed, reliquary, remembrance, ribbon, rod,
   rostral column, screw, screwing, shank, shoot, shrine, skyscraper,
   socle, spilehole, spiracle, spire, staff, stalk, stanchion, stand,
   standard, standpipe, steeple, stela, stem, stick, sting, stone,
   streak, stupa, subbase, surbase, tablet, television mast,
   testimonial, thrust, tomb, tombstone, tope, touchhole, tour, tower,
   transom, trophy, trunk, tunnel, turret, upright, vent, ventage,
   venthole, ventiduct, ventilating shaft, ventilator, volley,
   water tower, well, wind tunnel, windmill tower, workings,
   yawning abyss