Sudden desire (4)
'sudden desire' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for urge that I've seen before include "Advise strongly or prod" , "Advise earnestly, encourage to go on" , "Propel, drive onward" , "Yen" , "Impel, exhort" .)
'sudden desire' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for whim that I've seen before include "Fanciful impulse" , "Fanciful idea" , "Fancy, notion" , "fantastic creation from the past" , "Fad" .)