The most common and most likely answer to this crossword clue is the 10 letter word COUNTERACT
I've seen this crossword clue in The Times
C
O
U
N
T
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A
C
T
More clues leading to the result COUNTERACT
- Oppose United and, later, European entering formal agreement
- Neuter cat roughly on table-top
- Oppose matter, given time by court
- Check for something done in opposition before
- Oppose token performance
- Take steps to neutralise new trace on number
- Put a check on board’s decree
- Take steps against token performance
- Correct to oppose law
- Work against producing token performance
Buddy explains!

The straight part
We know that "Neuter" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case neuter = counteract.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 COUNTERACT mean?
COUNTERACT noun- An action performed in opposition to another action.
- To have a contrary or opposing effect or force on
- To deliberately act in opposition to, to thwart or frustrate