The most common and most likely answer to this crossword clue is the 7 letter word INVOLVE
I
N
V
O
L
V
E
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The straight part
We know that "Concern" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case concern = involve.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 INVOLVE mean?
INVOLVE verb- To roll or fold up; to wind round; to entwine.
- To envelop completely; to surround; to cover; to hide.
- To complicate or make intricate, as in grammatical structure.
- To connect with something as a natural or logical consequence or effect; to include necessarily; to imply.
- To take in; to gather in; to mingle confusedly; to blend or merge.
- To envelop, enfold, entangle.
- To engage (someone) to participate in a task.
- To raise to any assigned power; to multiply, as a quantity, into itself a given number of times.