Dictionary of Ichthyology  

oroshi hocho = in Japanese おろし包丁, meaning wholesale knife, a long (1.8 m including handle) and specialised knife used to fillet tuna and other large fishes. See also hancho hocho.

Tsukiji Fish Market from Wikimedia Commons: http://commons.wikimedia.org/wiki/File:Tsukiji_fish_market_thuna_knife.jpg

Canadian Museum of Nature
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