The Collaborative International Dictionary of English v.0.48:

Scythe \Scythe\ (s[imac]th), n. [OE. sithe, AS. s[imac][eth]e,
   sig[eth]e; akin to Icel. sig[eth]r a sickle, LG. segd, seged,
   seed, seid, OHG. segansa sickle, scythe, G. sense scythe, and
   to E. saw a cutting instrument. See Saw.] [Written also
   sithe and sythe.]
   1. An instrument for mowing grass, grain, or the like, by
      hand, composed of a long, curving blade, with a sharp
      edge, made fast to a long handle, called a snath, which is
      bent into a form convenient for use.
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            The sharp-edged scythe shears up the spiring grass.
                                                  --Drayton.
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            Whatever thing
            The scythe of Time mows down.         --Milton.
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   2. (Antiq.) A scythe-shaped blade attached to ancient war
      chariots.
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The Collaborative International Dictionary of English v.0.48:

Sithe \Sithe\, v. i. [Cf. Sigh.]
   To sigh.

   Note: [A spelling of a corrupt and provincial pronunciation.]
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The Collaborative International Dictionary of English v.0.48:

Sithe \Sithe\, n.
   A scythe. [Obs.] --Milton.
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The Collaborative International Dictionary of English v.0.48:

Sithe \Sithe\, v. t.
   To cut with a scythe; to scythe. [Obs.]
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The Collaborative International Dictionary of English v.0.48:

Sith \Sith\, Sithe \Sithe\, n. [AS. ??? a path, way, time,
   occasion.]
   Time. [Obs.] --Chaucer.
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         And humbly thanked him a thousand sithes. --Spenser.
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