The Collaborative International Dictionary of English v.0.48:

Curl \Curl\, v. i.
   1. To contract or bend into curls or ringlets, as hair; to
      grow in curls or spirals, as a vine; to be crinkled or
      contorted; to have a curly appearance; as, leaves lie
      curled on the ground.
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            Thou seest it [hair] will not curl by nature.
                                                  --Shak.
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   2. To move in curves, spirals, or undulations; to contract in
      curving outlines; to bend in a curved form; to make a curl
      or curls. "Cirling billows." --Dryden.
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            Then round her slender waist he curled. --Dryden.
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            Curling smokes from village tops are seen. --Pope.
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            Gayly curl the waves before each dashing prow.
                                                  --Byron.
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            He smiled a king of sickly smile, and curled up on
            the floor.                            --Bret Harte.
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   3. To play at the game called curling. [Scot.]
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The Collaborative International Dictionary of English v.0.48:

Curl \Curl\ (k[^u]rl), v. t. [imp. & p. p. Curled (k[^u]rld);
   p. pr. & vb. n. Curling.] [Akin to D. krullen, Dan.
   kr["o]lle, dial. Sw. krulla to curl, crisp; possibly akin to
   E. crook. Cf. Curl, n., Cruller.]
   1. To twist or form into ringlets; to crisp, as the hair.
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            But curl their locks with bodkins and with braid.
                                                  --Cascoigne.
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   2. To twist or make onto coils, as a serpent's body.
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            Of his tortuous train,
            Curled many a wanton wreath in sight of Eve.
                                                  --Milton.
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   3. To deck with, or as with, curls; to ornament.
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            Thicker than the snaky locks
            That curledMeg[ae]ra.                 --Milton.
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            Curling with metaphors a plain intention. --Herbert.
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   4. To raise in waves or undulations; to ripple.
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            Seas would be pools without the brushing air
            To curl the waves.                    --Dryden.
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   5. (Hat Making) To shape (the brim) into a curve.
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The Collaborative International Dictionary of English v.0.48:

Curl \Curl\ (k[^u]rl), n. [Akin to D. krul, Dan. kr["o]lle. See
   Curl, v. ]
   1. A ringlet, especially of hair; anything of a spiral or
      winding form.
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            Under a coronet, his flowing hair
            In curls on either cheek played.      --Milton.
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   2. An undulating or waving line or streak in any substance,
      as wood, glass, etc.; flexure; sinuosity.
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            If the glass of the prisms . . . be without those
            numberless waves or curls which usually arise from
            the sand holes.                       --Sir I.
                                                  Newton.
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   3. A disease in potatoes, in which the leaves, at their first
      appearance, seem curled and shrunken.
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   Blue curls. (Bot.) See under Blue.
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WordNet (r) 3.0 (2006):

curl
    n 1: a round shape formed by a series of concentric circles (as
         formed by leaves or flower petals) [syn: coil, whorl,
         roll, curl, curlicue, ringlet, gyre, scroll]
    2: American chemist who with Richard Smalley and Harold Kroto
       discovered fullerenes and opened a new branch of chemistry
       (born in 1933) [syn: Curl, Robert Curl, Robert F. Curl,
       Robert Floyd Curl Jr.]
    3: a strand or cluster of hair [syn: lock, curl, ringlet,
       whorl]
    v 1: form a curl, curve, or kink; "the cigar smoke curled up at
         the ceiling" [syn: curl, curve, kink]
    2: shape one's body into a curl; "She curled farther down under
       the covers"; "She fell and drew in" [syn: curl up, curl,
       draw in]
    3: wind around something in coils or loops [syn: coil, loop,
       curl] [ant: uncoil]
    4: twist or roll into coils or ringlets; "curl my hair, please"
       [syn: curl, wave]
    5: play the Scottish game of curling