The most common and most likely answer to this crossword clue is the 10 letter word GOOSEBERRY
I've seen this crossword clue in Financial Times
G
O
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S
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More clues leading to the result GOOSEBERRY
- Bird we're told put six feet under bush
- Kind of tart whose company’s not wanted
- That’s the third person who’s not wanted fruit
- Fruit no lovers want?
- Poke Chuck in bottom. His company’s not wanted
- One watches pair getting fruity pie full of this?
- I often hang around fruit
- Third party?
- Duo’s accompanist won’t enjoy playing this
- So beer casually drunk by murderous, unwanted companion of lovers
Buddy explains!

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 GOOSEBERRY mean?
GOOSEBERRY noun- A fruit, Ribes uva-crispa, related to the currant.
- Any other plant or fruit in the subgenus Grossularia, distinguished from currants by bearing spines, including Ribes hirtellum, the American gooseberry.
- Any of several other plants that are not closely related but bear fruit in some way similar:
- (British slang) A chaperone.
- An additional person who is neither necessary nor wanted in a given situation.
- (British slang) A fool.
- (British slang) A fantastic story; a tall tale; a hoax.
- (British slang, usually in the plural) A testicle.