The Collaborative International Dictionary of English v.0.48:

Melon \Mel"on\ (m[e^]l"[u^]n), n. [F., fr. L. melo, for melopepo
   an apple-shaped melon, Gr. mhlope`pwn; mh^lon apple + pe`pwn
   a species of large melon; cf. L. malum apple. Cf.
   Marmalade.]
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   1. (Bot.) The juicy fruit of certain cucurbitaceous plants,
      as the muskmelon, watermelon, and citron melon; also, the
      plant that produces the fruit.
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   2. (Zool.) A large, ornamental, marine, univalve shell of the
      genus Melo.
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   Melon beetle (Zool.), a small leaf beetle (Diabrotiea
      vittata), which damages the leaves of melon vines.

   Melon cactus, Melon thistle.
      (a) (Bot.) A genus of cactaceous plants (Melocactus)
          having a fleshy and usually globose stem with the
          surface divided into spiny longitudinal ridges, and
          bearing at the top a prickly and woolly crown in which
          the small pink flowers are half concealed. Melocactus
          communis, from the West Indies, is often cultivated,
          and sometimes called Turk's cap.
      (b) The related genus Mamillaria, in which the stem is
          tubercled rather than ribbed, and the flowers
          sometimes large. See Illust. under Cactus.
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The Collaborative International Dictionary of English v.0.48:

Turk \Turk\ (t[^u]rk), n. [Per. Turk; probably of Tartar origin:
   cf. F. Turc.]
   1. A member of any of numerous Tartar tribes of Central Asia,
      etc.; esp., one of the dominant race in Turkey.
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   2. A native or inhabitant of Turkey.
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   3. A Muslim; esp., one living in Turkey. [Archaic]
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            It is no good reason for a man's religion that he
            was born and brought up in it; for then a Turk would
            have as much reason to be a Turk as a Christian to
            be a Christian.                       --Chillingworth.
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   4. (Zool.) The plum weevil. See Curculio, and Plum
      weevil, under Plum.
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   Turk's cap. (Bot.)
      (a) Turk's-cap lily. See under Lily.
      (b) A tulip.
      (c) A plant of the genus Melocactus; Turk's head. See
          Melon cactus, under Melon.

   Turk's head.
      (a) (Naut.) A knot of turbanlike form worked on a rope
          with a piece of small line. --R. H. Dana, Jr.
      (b) (Bot.) See Turk's cap
      (c) above.

   Turk's turban (Bot.), a plant of the genus Ranunculus;
      crowfoot.
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