The term 'FISHING ROD SPOOL' is a crossword solution that refers to the REEL, which is a four-letter word. A fishing rod spool is a cylindrical device attached to a fishing rod that holds the line and allows it to be released or reeled in. It is usually made of metal, plastic, or wood, and is designed to rotate freely when the line is pulled. The spool also helps to keep the line from tangling and provides a smooth release of the line when casting.