The most common and most likely answer to this crossword clue is the 10 letter word DESPATCHED
I've seen this crossword clue in The Daily Telegraph
D
E
S
P
A
T
C
H
E
D
Buddy explains!
The straight part
We know that "sent packing" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sent packing = despatched.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does DESPATCHED mean?
DESPATCHED verb- To send (a shipment) with promptness.
- To send (a person) away hastily.
- To send (an important official message) promptly, by means of a diplomat or military officer.
- To send (a journalist) to a place in order to report.
- To dispose of speedily, as business; to execute quickly; to make a speedy end of; to finish; to perform.
- To rid; to free.
- To destroy quickly and efficiently.
- To pass on for further processing, especially via a dispatch table (often with to).
- To hurry.
- To deprive.