[thresher shark] n (1888): a large nearly cosmopolitan shark (Alopias vulpinus) having a greatly elongated curved upper lobe of its tail with which it is said to thresh the water to round up the fish on which it feeds--see shark illustration
THRESHER SHARK
Meaning of THRESHER SHARK in English
Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012