The most common and most likely answer to this crossword clue is the 7 letter word DENSEST
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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 DENSEST mean?
DENSEST adjective- Having relatively high density.
- Compact; crowded together.
- Thick; difficult to penetrate.
- Opaque; allowing little light to pass through.
- Obscure, or difficult to understand.
- Being a subset of a topological space that approximates the space well. See Wikipedia article on dense sets for mathematical definition.
- (of a person) Slow to comprehend; of low intelligence.