A transom is the aft transverse surface of the hull of some boats and ships forming its stern. Adding both strength and width to the stern, a transom may be flat or curved, and vertical, raked aft (known as an overhung or "counter" stern), or raked forward (and "reversed",^[1] also known as retroussé).^[2] In small boats and yachts, a flat termination of the stern is typically above the waterline, but large commercial vessels often exhibit vertical transoms that dip slightly beneath the water.^[3]

On smaller boats such as dinghies, transoms may be used to support a rudder, outboard motor, or other accessory. On some yachts the transom may include a hinged swim platform, and a lazarette for deck items and leisure toys.^[4]

Etymology

The term was used as far back as Middle English in the 1300s, having come from Latin transversus (transverse) via Old French traversain (set crosswise).^[2][5]

History

This section needs expansion with: content on the evolution of the transom over time. You can help by adding missing information. (August 2025)

Design

This section needs expansion with: the advantages and disadvantages of transoms, and the pros and cons of each design. You can help by adding missing information. (August 2025)

Gallery

• 
  Flat transom on a dinghy with rudder mounting points
• 
  The transom of the Spirit of Bermuda, made of Bermuda cedar
• 
  Raked transom with rudder mounting points
• 
  Reverse transom with rudder mounted under the hull
• 
  Transom-mounted outboard motor
• 
  An Irwin 44 sloop with a fold-down reverse transom
• 
  Reverse transom with integral access platform

References