White"cap

from WordNet (r) 3.0 (2006)

whitecap
    n 1: a wave that is blown by the wind so its crest is broken and
         appears white [syn: {whitecap}, {white horse}]

from The Collaborative International Dictionary of English v.0.48

Whitecap \White"cap`\, n.
   1. (Zool.)
      (a) The European redstart; -- so called from its white
          forehead.
      (b) The whitethroat; -- so called from its gray head.
      (c) The European tree sparrow.
          [1913 Webster]

   2. A wave whose crest breaks into white foam, as when the
      wind is freshening.
      [1913 Webster]

   3. A member of a self-appointed vigilance committee
      attempting by lynch-law methods to drive away or coerce
      persons obnoxious to it. Some early ones wore white hoods
      or masks. [U. S.] -- {White"cap`}, v. -- {White"cap`per},
      n.
      [Webster 1913 Suppl.]

from The Collaborative International Dictionary of English v.0.48

Whitethroat \White"throat`\, n. (Zool.)
   Any one of several species of Old World warblers, esp. the
   common European species ({Sylvia cinerea}), called also
   {strawsmear}, {nettlebird}, {muff}, and {whitecap}, the
   {garden whitethroat}, or {golden warbler} ({Sylvia
   hortensis}), and the {lesser whitethroat} ({Sylvia curruca}).
   [1913 Webster]