The most common and most likely answer to this crossword clue is the 13 letter word COLLABORATION
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More clues leading to the result COLLABORATION
- Working together, almost arrest bishop before speech
- Left workplace with speech on company teamwork
- Speech backing firm Lib-Lab partnershipÂ
- Not a single job in Scottish island: a premature cancellation all round
- Sailor comes to Scottish island with speech — gets folk working together
- Alliance taking company line prior to Labour speech
- Joint work by fifty in company science room, with speech following
Buddy explains!

The straight part
We know that "Joint work" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case joint work = collaboration.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 COLLABORATION mean?
COLLABORATION noun- The act of collaborating.
- A production or creation made by collaborating.
- Treasonous cooperation.