Merriam-Webster Collegiate Dictionary - scull

 I. noun  Etymology: Middle English skulle  Date: 14th century  1.  a. an oar used at the stern of a boat to propel it forward with a thwartwise motion  b. either of a pair of oars usually less than 10 feet (3 meters) in length and operated by one person  2. a racing shell propelled by one or two persons using ~s  II. verb  Date: 1624  transitive verb to propel (a boat) by ~s or by a large oar worked thwartwise  intransitive verb to ~ a boat  • ~er noun