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twibill

American  
[twahy-bil] / ˈtwaɪˌbɪl /

noun

  1. a mattock with one arm like that of an adze and the other like that of an ax.

  2. Archaic. a double-bladed battle-ax.


twibill British  
/ ˈtwaɪˌbɪl /

noun

  1. a mattock with a blade shaped like an adze at one end and like an axe at the other

  2. archaic a double-bladed battle-axe

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of twibill

First recorded before 1000; Middle English, Old English; see twi-, bill 3