Stern refers to the aft part of a boat - the back of the boat.
Stern light is described as a white running light placed at the stern of the boat. The stern light should be visible through an arc of 135?, to the rear of the boat.
Stern line is relating to a line running from the stern of the boat to a dock when moored.
See also:
"Stern" is in the UNSPSC Code "25111931"
Stern platforms
Ref: 122268/2006-10-09