The term 'Pair in a Rowboat' can be solved by the four-letter word 'OARS'. OARS are long, thin poles used to propel a boat through the water. They are usually held by the rower and used to push against the water in order to move the boat forward. OARS are commonly used in rowboats, which are small boats designed for one or two people. A pair of OARS is necessary for a rowboat to move, as it provides the power needed to propel the boat.