The most common and most likely answer to this crossword clue is the 10 letter word EQUILIBRIA
I've seen this crossword clue in The Guardian
E
Q
U
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L
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A
Buddy explains!

The straight part
We know that "balances" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case balances = equilibria.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 EQUILIBRIA mean?
EQUILIBRIA noun- The condition of a system in which competing influences are balanced, resulting in no net change.
- Mental balance.
- The state of a reaction in which the rates of the forward and reverse reactions are the same.
- The state of a body at rest or in uniform motion in which the resultant of all forces on it is zero.