A flow stopper is an object or device that is used to prevent the flow of a liquid or gas. The crossword solutions for the term 'flow stopper' are JAM (3 letters), CLOT (4 letters), DAM (3 letters), and CLOG (4 letters). JAM is a thick, sticky substance made from fruit and sugar that can be used to block a pipe or other opening. CLOT is a mass of solidified blood that can form in a vein or artery and block the flow of blood. DAM is a barrier built across a river or other body of water to control the flow of water. CLOG is an obstruction in a pipe or other opening that prevents the flow of liquid or gas.