The most common and most likely answer to this crossword clue is the 7 letter word IMPENDS
I
M
P
E
N
D
S
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The straight part
We know that "looms" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case looms = impends.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 IMPENDS mean?
IMPENDS verb- To hang or be suspended over (something); to overhang.
- Figuratively to hang over (someone) as a threat or danger.
- To threaten to happen; to be about to happen, to be imminent.
- To pay.