The most common and most likely answer to this crossword clue is the 3 letter word ADA
I've seen this crossword clue in Independent
A
D
A
More clues leading to the result ADA
- A prosecuting officer’s girl
- Chap’s dropping masculine woman
- Helpful-sounding woman
- In hearing, assist a woman
- A US lawyer’s high-level language
- Woman’s only notes from Quai d’Orsay
- Leading parts for actress and daughter playing woman who doesn’t know whether she’s coming or going
- Language having little advantage to American
- Pioneering programmer needs a lawyer
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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.