Cryptic crossword clue
Superior class functioning brilliantly 2,3,4

The most common and most likely answer to this crossword clue is the 2 plus 3 plus 4 letter word ON TOP FORM

I've seen this crossword clue in Financial Times
O
N
T
O
P
F
O
R
M

Buddy explains!

The straight part
We know that "functioning brilliantly" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case functioning brilliantly = on top form.
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.

Crossword Answer definitions

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