The most common and most likely answer to this crossword clue is the 9 letter word IMITATIVE
I've seen this crossword clue in The Times
I
M
I
T
A
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More clues leading to the result IMITATIVE
- Echoing musical notes ascending
- Mimicking cry of kid at play a president’s wife’s mounted
- This person’s one with rubbish – this person’s not original
- Fake vitamin: Norway aside, it’s manufactured by Europe
- I am the answer to your prayers, existing to have time for learner’s copying
- Former president’s wife, almost afraid to be rejected for copying him?
- I married one, a vet — it turns out to be not the real thing
- ‘Not original‘ — university musical reviewed by Independent
- Echoing musical with two notes raised
Buddy explains!

The straight part
We know that "Mimicking" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case mimicking = imitative.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 IMITATIVE mean?
IMITATIVE adjective- Imitating; copying; not original.
- Modelled after another thing.