Should (5,2)
'should' is the definition.
(synonyms)
This is the entire clue.
(Other definitions for ought that I've seen before include "Tough (anag)" , "Have/has a duty (to do)" , "It expresses duty or obligation" , "outdated anything at all?" , "Be bound" .)
'should' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Another definition for ought to that I've seen is " Should".)