Feature about old bit of rope (5)
I believe the answer is:
noose
'rope' is the definition.
(noose is a kind of rope)
'feature about old bit of' is the wordplay.
'feature' becomes 'nose' (I've seen this before).
'about' means one lot of letters goes inside another.
'bit of' says to take the initial letters.
The initial letter of 'old' is 'o'.
'nose' going around 'o' is 'NOOSE'.
(Other definitions for noose that I've seen before include "Hangman's knot" , "Hangman's or cowboy's loop" , "Hangman's equipment" , "Loop of rope with a slipknot" , "Loop in rope that tightens when pulled" .)