from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A disk turning on a diametrical axis inside a pipe, used as a throttle valve or damper.
- n. A valve composed of two semicircular plates hinged on a common spindle, used to permit flow in one direction only.
from the GNU version of the Collaborative International Dictionary of English
- n. a kind of double clack valve, consisting of two semicircular clappers or wings hinged to a cross rib in the pump bucket. When open it somewhat resembles a butterfly in shape.
from The Century Dictionary and Cyclopedia
- n. A kind of double clack-valve used in pumps.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a valve in a carburetor that consists of a disc that turns and acts as a throttle
Sorry, no etymologies found.