Laborious effort (7)
I believe the answer is:
travail
'laborious effort' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for travail that I've seen before include "In old use, the pains of childbirth" , "Hard work" , "Labour, toil" , "Exertion, elbow grease" , "Painful or laborious effort, like childbirth" .)