Railway carriage (5)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">railway carriage</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I know that sleeper is a type of railway carriage)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for sleeper that I've seen before include "found on the railway" , "night train" , "Spy; part of railway" , "Railway track support" , "Beam across railway track or berth on ship" .)
(Other definitions for coach that I've seen before include "Train - or part of one!" , "Railway carriage or sports instructor" , "Teacher of sporting activity" , "Trainer - vehicle" , "Vehicle; instructor" .)