The most common and most likely answer to this crossword clue is the 9 letter word VOLUNTEER
I've seen this crossword clue in The Guardian
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More clues leading to the result VOLUNTEER
- Suggest true love doesn't run smooth around November
- One can’t be forced to work
- Layabout lout never one to offer help freely
- Offer to tour elven ruins
- Offer to work for no money
- Terrier for one in novel true to form
- Left, intervening in UN veto, about … about … about to step forward
- Lively tune penned by lover bursting to propose
- True love motivation ultimately for this person working?
- True novel about being in army?
Buddy explains!

The straight part
We know that "Offer/to work for no money" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case offer/to work for no money = volunteer.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 VOLUNTEER mean?
VOLUNTEER noun- One who enters into, or offers for, any service of his/her own free will, especially when done without pay.
- One who enters into military service voluntarily, but who, when in service, is subject to discipline and regulations like other soldiers; -- opposed to conscript; specifically, a voluntary member of the organized militia of a country as distinguished from the standing army.
- A person who acts out of his own will without a legal obligation, such as a donor.
- A plant that grows spontaneously, without being cultivated on purpose; see volunteer plant in Wikipedia.
- A native or resident of the American state of Tennessee.
- To enlist oneself as a volunteer.
- To do or offer to do something voluntarily.
- To offer, usually unprompted.
- To grow without human sowing or intentional cultivation.
- To offer the services of (someone else) to do something.