The most common and most likely answer to this crossword clue is the 8 letter word INCURRED
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The straight part
We know that "brought upon oneself" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case brought upon oneself = incurred.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 INCURRED mean?
INCURRED verb- To bring upon oneself or expose oneself to, especially something inconvenient, harmful, or onerous; to become liable or subject to
- To enter or pass into
- To fall within a period or scope; to occur; to run into danger