Girl with nothing but some rope (5)
I believe the answer is:
lasso
'some rope' is the definition.
(lasso is a kind of rope)
'girl with nothing' is the wordplay.
'girl' becomes 'lass' (lass can informally mean a girl).
'with' says to put letters next to each other.
'nothing' becomes 'O' (looks like zero - 0).
'lass'+'o'='LASSO'
'but' is the link.
(Other definitions for lasso that I've seen before include "Nosed rope" , "A cowboy's rope with a running noose" , "Rope with noose for catching animals" , "snare" , "Belgian composer" .)