Lash it back with a rope's end! (3)
I believe the answer is:
tie
'lash' is the definition.
(I know that lash is a more specific form of the action the tie)
'it back with a rope's end' is the wordplay.
'back' says the letters should be written backwards.
'with' says to put letters next to each other.
'end' indicates one should take the final letters.
The last letter of 'rope' is 'e'.
'it' backwards is 'ti'.
'ti'+'e'='TIE'
(Other definitions for tie that I've seen before include "Form into a knot or bow" , "Restrict; link" , "Bond > girl wearing this? Unlikely" , "Bind; knot" , "oblige" .)