The term SWIMMING POOL PART can be summarized as 'LINER', which is a five-letter word. A LINER is a thin sheet of material that is used to line the walls and floor of a swimming pool. It is typically made of vinyl, rubber, or fiberglass and is designed to protect the pool from water loss and to keep the pool clean. Liners are also used to add aesthetic appeal to a pool, as they come in a variety of colors and patterns.