The Collaborative International Dictionary of English v.0.48:

Tiller \Till"er\, n. [From OE. tillen, tullen, to draw, pull;
   probably fr. AS. tyllan in fortyllan to lead astray; or cf.
   D. tillen to lift up. Cf. Till a drawer.]
   1. (Naut.) A lever of wood or metal fitted to the rudder head
      and used for turning side to side in steering. In small
      boats hand power is used; in large vessels, the tiller is
      moved by means of mechanical appliances. See Illust. of
      Rudder. Cf. 2d Helm, 1.
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   2. The stalk, or handle, of a crossbow; also, sometimes, the
      bow itself. [Obs.]
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            You can shoot in a tiller.            --Beau. & Fl.
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   3. The handle of anything. [Prov. Eng.]
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   4. A small drawer; a till. --Dryden.
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   Tiller rope (Naut.), a rope for turning a tiller. In a
      large vessel it forms the connection between the fore end
      of the tiller and the steering wheel.
      [1913 Webster] Tilley