scull / skull are similar-sounding terms with different meanings (referred to as homophones). To better understand the differences, see below for definitions, pronunciation guides, and example sentences using each term. 👇
scull: (noun) a long oar that is mounted at the stern of a boat and moved left and right to propel the boat forward. (noun) each of a pair of short oars that are used by a single oarsman. (noun) a racing shell that is propelled by sculls. (verb) propel with sculls.
skull: (noun) the bony skeleton of the head of vertebrates.
scull: s·k·AH·l
skull: s·k·AH·l
(Examples are Wikipedia snippets under the CC ShareAlike 3.0 license. Definitions drawn from WordNet.)