This little girl needs only a moment to finish (3)

I believe the answer is:

bea

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'only a moment to finish' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'this little girl needs' is the wordplay.
'this little' means to remove the last letter (the word is not quite complete).
'girl' becomes 'bet'.
'needs' becomes 'a' (I can't explain this - if you can you should believe this answer much more).
'bet' with its final letter removed is 'be'.
'be'+'a'='BEA'

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