clack valve
noun
a valve having a hinged flap permitting flow only in the direction in which the flap opens.
Also called
flap valve.
Origin of clack valve
First recorded in 1855–60
Words nearby clack valve
clabber,
clabber cheese,
clabby-doo,
clachan,
clack,
clack valve,
clacker,
clackers,
clackmannan,
clackmannanshire,
clacton