The Collaborative International Dictionary of English v.0.48:

Lash \Lash\ (l[a^]sh), n. [OE. lasche; cf. D. lasch piece set
   in, joint, seam, G. lashe latchet, a bit of leather, gusset,
   stripe, laschen to furnish with flaps, to lash or slap, Icel.
   laski gusset, flap, laska to break.]
   1. The thong or braided cord of a whip, with which the blow
      is given.
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            I observed that your whip wanted a lash to it.
                                                  --Addison.
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   2. A leash in which an animal is caught or held; hence, a
      snare. [Obs.]
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   3. A stroke with a whip, or anything pliant and tough; as,
      the culprit received thirty-nine lashes.
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   4. A stroke of satire or sarcasm; an expression or retort
      that cuts or gives pain; a cut.
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            The moral is a lash at the vanity of arrogating that
            to ourselves which succeeds well.     --L'Estrange.
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   5. A hair growing from the edge of the eyelid; an eyelash.
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   6. In carpet weaving, a group of strings for lifting
      simultaneously certain yarns, to form the figure.
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The Collaborative International Dictionary of English v.0.48:

Lash \Lash\, v. i.
   To ply the whip; to strike; to utter censure or sarcastic
   language.
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         To laugh at follies, or to lash at vice. --Dryden.
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   To lash out, to strike out wildly or furiously; also used
      figuratively.
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The Collaborative International Dictionary of English v.0.48:

Lash \Lash\, v. t. [Cf. D. lasschen to fasten together, lasch
   piece, joint, Sw. laska to stitch, Dan. laske stitch. See
   Lash, n. ]
   To bind with a rope, cord, thong, or chain, so as to fasten;
   as, to lash something to a spar; to lash a pack on a horse's
   back.
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The Collaborative International Dictionary of English v.0.48:

Lash \Lash\ (l[a^]sh), v. t. [imp. & p. p. Lashed; p. pr. &
   vb. n. Lashng.]
   1. To strike with a lash; to whip or scourge with a lash, or
      with something like one.
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            We lash the pupil, and defraud the ward. --Dryden.
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   2. To strike forcibly and quickly, as with a lash; to beat,
      or beat upon, with a motion like that of a lash; as, a
      whale lashes the sea with his tail.
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            And big waves lash the frighted shores. --Dryden.
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   3. To throw out with a jerk or quickly.
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            He falls, and lashing up his heels, his rider
            throws.                               --Dryden.
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   4. To scold; to berate; to satirize; to censure with
      severity; as, to lash vice.
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WordNet (r) 3.0 (2006):

lash
    n 1: any of the short curved hairs that grow from the edges of
         the eyelids [syn: eyelash, lash, cilium]
    2: leather strip that forms the flexible part of a whip [syn:
       lash, thong]
    3: a quick blow delivered with a whip or whiplike object; "the
       whip raised a red welt" [syn: whip, lash, whiplash]
    v 1: beat severely with a whip or rod; "The teacher often
         flogged the students"; "The children were severely
         trounced" [syn: flog, welt, whip, lather, lash,
         slash, strap, trounce]
    2: lash or flick about sharply; "The lion lashed its tail"
    3: strike as if by whipping; "The curtain whipped her face"
       [syn: whip, lash]
    4: bind with a rope, chain, or cord; "lash the horse" [ant:
       unlash]