The most common and most likely answer to this crossword clue is the 5 plus 5 letter word ROUND ROBIN
I've seen this crossword clue in The Guardian
R
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More clues leading to the result ROUND ROBIN
- Where the merry men gathered for a letter?
- Where merry men gathered to play with each other
- Letter signed by many on all sides seen by 4’s partner
- Message for all to endorse in plump Christmas bird
- Plump bird associated with Christmas competition
- Type of ferry carrying German and British during competition
- Where Hood’s men gathered petition?
- Plump bird that’s become part of Christmas for some
- Some drinks run out by receptacle in tournament?
- Plump boy’s petition
Buddy explains!
The straight part
We know that "Message for all to endorse" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case message for all to endorse = round robin.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 ROUND ROBIN mean?
ROUND ROBIN noun- The part of a tournament in which every player or team competes against each of the others in turn.
- A petition signed in a circular fashion to disguise the order in which it was done.
- A letter, with copies to multiple recipients, usually at Christmastime and often enclosed with a card, giving family news of interest to the sender.
- A method of dividing loot amongst a party of players by having the game assign in turn loot to a player or an enemy corpse to loot to a player.
- A form of trade, wherein a stamp collector sends a packet of stamps to the next person on a list, who then takes the stamps he wants, replacing them with like-valued stamps, and then passing the packet to the next person on the list, until the packet ultimately returns to the original sender.
- A method of dividing labor between several similar subsystems, assigning tasks to each of them in turn in an attempt to use resources more equitably.