Dour general conceals desire (4)
I believe the answer is:
urge
'desire' is the definition.
(I know that urge is a type of desire)
'dour general conceals' is the wordplay.
'conceals' says the answer is hidden in the clue.
'URGE' is hidden within 'dour general'.
(Other definitions for urge that I've seen before include "Strongly recommend; impulse" , "Appeal to" , "Advise earnestly, spur" , "Impel, exhort" , "Impel - impulse" .)