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butterfly valve

noun
  1. a clack valve having two flaps with a common hinge.
  2. a valve, as the throttle valve in a carburetor, that swings about a central axis across its face.

Origin of butterfly valve

First recorded in 1860–65
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for butterfly valve

butterfly valve

noun
  1. a disc that acts as a valve by turning about a diameter, esp one used as the throttle valve in a carburettor
  2. a non-return valve consisting of two semicircular plates hinged about a common central spindle
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