Breathtaking feature, including old hangman's loop (5)
I believe the answer is:
noose
'hangman's loop' is the definition.
(I've seen this in another clue)
'breathtaking feature including old' is the wordplay.
I cannot really understand how this works, but
'old' could be 'o' (abbreviation) and 'o' is found within the answer.
'feature' could be 'nose' (a facial feature) and 'nose' is found in the remaining letters.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for noose that I've seen before include "Hangman's running loop" , "Hangman's knot" , "Loop of rope with a slipknot" , "Hanging material" , "Hangman's or cowboy's loop" .)