ra·zor·back /ˈrezɚ/
  狹尖的背脊,剃刀鯨,剃刀的鋒口,鮮明的分界線,緊急關頭
  Ra·zor·back n. Zool. The rorqual.
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  razorback
       adj : having a sharp narrow back; "a razor-backed horse";
             "razorback hogs" [syn: razor-backed]
       n 1: a mongrel hog with a thin body and long legs and a ridged
            back; a wild or semi-wild descendant of improved breeds;
            found chiefly in the southeastern United States [syn: razorback
            hog, razorbacked hog]
       2: any of several baleen whales of the family Balaenopteridae
          having longitudinal grooves on the throat and a small
          pointed dorsal fin [syn: rorqual]