Off course like a platter (6)
I believe the answer is:
astray
'off course' is the definition.
(to be led astray is to be led off course)
'like a platter' is the wordplay.
'like' becomes 'as'.
'a platter' becomes 'tray' (tray for food).
'as'+'tray'='ASTRAY'
(Other definitions for astray that I've seen before include "wide of the mark" , "Adrift - misguided - lost" , "Off the correct path" , "Gone off the right path" , "Up the garden path?" .)