Sideways on a ship (5)
I believe the answer is:
abeam
'sideways on a ship' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for abeam that I've seen before include "going from one side to the other" , "The way sailor goes across ship" , "Position relative to ship" , "from side to side on voyage?" , "at right angles to vessel" .)