The most common and most likely answer to this crossword clue is the 12 letter word STRENGTHENED
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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 STRENGTHENED mean?
STRENGTHENED verb- To make strong or stronger; to add strength to; to increase the strength of; to fortify.
- To empower; to give moral strength to; to encourage; to enhearten.
- To augment; to improve; to intensify.
- To grow strong or stronger.