The most common and most likely answer to this crossword clue is the 6 letter word SNOTTY
S
N
O
T
T
Y
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The straight part
We know that "proud" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case proud = snotty.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 SNOTTY mean?
SNOTTY noun- The lion's mane jellyfish, which secretes a mucus that can foul fishing nets.
- Running or dirtied with snot.
- Resembling or characteristic of snot, especially in texture.
- Ill-tempered or impertinent in an arrogant, conceited manner.