Comet feature
I believe the answer is:
tail
'comet feature' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for tail that I've seen before include "weaker batsmen" , "Follow furtively like private detective" , "part of coat" , "Elongated posterior part of an animal" , "Flexible part that extends from an animal's rear" .)