sluice valve(n = noun.artifact) floodgate, head gate, penstock, sluicegate, water gate - regulator consisting of a valve or gate that controls the rate of water flow through a sluice;
is a kind of regulator
is a part of penstock, sluice, sluiceway

aortic valve, atrioventricular valve, ball valve, bicuspid valve, blow valve, butterfly valve, cardiac valve, clack valve, clapper valve, escape valve, exhaust valve, foot valve, heart valve, ileocecal valve, intake valve, kingston valve, left atrioventricular valve, mitral valve, mitral valve prolapse, mitral valve stenosis, pilot valve, poppet valve, pulmonary valve, pyloric valve, rectifying valve, relief valve, right atrioventricular valve, safety valve, semilunar valve, shunt valve, slide valve, sluice, sluice down, thermionic valve, throttle valve, tricuspid valve, valve, valve rocker