The Collaborative International Dictionary of English v.0.48:

Stile \Stile\, n. [See Style.]
   1. A pin set on the face of a dial, to cast a shadow; a
      style. See Style. --Moxon.
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   2. Mode of composition. See Style. [Obs.]
      [1913 Webster]

            May I not write in such a stile as this? --Bunyan.
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The Collaborative International Dictionary of English v.0.48:

Stile \Stile\, n. [OE. stile, AS. stigel a step, a ladder, from
   st[imac]gan to ascend; akin to OHG. stigila a stile.
   [root]164. See Sty, v. i., and cf. Stair.]
   1. A step, or set of steps, for ascending and descending, in
      passing a fence or wall.
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            There comes my master . . . over the stile, this
            way.                                  --Shak.
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            Over this stile in the way to Doubting Castle.
                                                  --Bunyan.
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   2. (Arch.) One of the upright pieces in a frame; one of the
      primary members of a frame, into which the secondary
      members are mortised.
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   Note: In an ordinary door the principal upright pieces are
         called stiles, the subordinate upright pieces mullions,
         and the crosspieces rails. In wainscoting the principal
         pieces are sometimes called stiles, even when
         horizontal.
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   Hanging stile, Pulley stile. See under Hanging, and
      Pulley.
      [1913 Webster]

WordNet (r) 3.0 (2006):

stile
    n 1: an upright that is a member in a door or window frame

Moby Thesaurus II by Grady Ward, 1.0:

67 Moby Thesaurus words for "stile":
   French door, Samson post, archway, back door, back stairs,
   baluster, balustrade, banister, barway, bulkhead,
   carriage entrance, cellar door, cellarway, companion, companionway,
   door, doorjamb, doorpost, doorway, escalier, fire escape,
   flight of steps, front door, gate, gatepost, gateway, hatch,
   hatchway, hitching post, incline, jamb, king post, landing,
   landing stage, lintel, milepost, mullion, perron, porch, portal,
   porte cochere, post, postern, propylaeum, pylon, ramp, scuttle,
   side door, signpost, snubbing post, spiral staircase, staircase,
   stairs, stairway, stanchion, standard, stepping-stones, steps,
   storm door, threshold, tollgate, trap, trap door,
   treads and risers, turnpike, turnstile, upright