The Collaborative International Dictionary of English v.0.48:

Pegador \Pe`ga*dor"\, n. [Sp., a sticker.] (Zool.)
   A species of remora (Echeneis naucrates). See Remora.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Remora \Rem"o*ra\ (r?m"?*r?), n. [L.: cf. F. r['e]mora.]
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   1. Delay; obstacle; hindrance. [Obs.] --Milton.
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   2. (Zool.) Any one of several species of fishes belonging to
      Echeneis, Remora, and allied genera. Called also
      sucking fish.
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   Note: The anterior dorsal fin is converted into a large
         sucking disk, having two transverse rows of lamellae,
         situated on the top of the head. They adhere firmly to
         sharks and other large fishes and to vessels by this
         curious sucker, letting go at will. The pegador, or
         remora of sharks (Echeneis naucrates), and the
         swordfish remora (Remora brachyptera), are common
         American species.
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   3. (Surg.) An instrument formerly in use, intended to retain
      parts in their places. --Dunglison.
      [1913 Webster]

WordNet (r) 3.0 (2006):

Echeneis naucrates
    n 1: remoras found attached to sharks [syn: sharksucker,
         Echeneis naucrates]