This emblem is a tailless animal (5)
I believe the answer is:
badge
'this emblem' is the definition.
(badge is a kind of emblem)
'tailless animal' is the wordplay.
'tailless' means to remove the last letter (the tail of the word is removed).
'animal' becomes 'badger' (I've seen this before).
'badger' with its final letter taken away is 'BADGE'.
'is a' is the link.
(Other definitions for badge that I've seen before include "Distinguishing emblem" , "Label with name or status" , "medal" , "Identifying emblem" , "evidence of membership" .)