### Clue: Rabbit, one with long ears eating very last bit of celery (6)
### Answer: HARVEY 
 ### Explanation: Definition: Rabbit
An envelope ('eating') of V ('very') in HARE ('one with long ears') plus Y ('last bit of celer**Y**'). Harvey was the eponymous invisible rabbit in the play by Mary Chase, and the better-known film based on it, and starring James Stewart.