The term 'Sink Plumbing Piece' refers to a TRAP, which is a four-letter word. A TRAP is a type of plumbing fitting that is installed in the drain line of a sink or other plumbing fixture. It is designed to prevent sewer gases from entering the home and to keep small objects from entering the drain line. Traps also help to maintain water pressure in the drain line, which helps to keep the sink draining properly.