Tailless animal arrived (4)
I believe the answer is:
came
'arrived' is the definition.
(coming is a kind of arriving)
'tailless animal' is the wordplay.
'tailless' means to remove the last letter.
'animal' becomes 'camel' (I've seen this before).
'camel' with its final letter taken away is 'CAME'.
(Other definitions for came that I've seen before include "Arrived" , "Appeared" .)