The most common and most likely answer to this crossword clue is the 13 letter word CONCENTRATION
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More clues leading to the result CONCENTRATION
Buddy explains!
The straight part
We know that "Deep thought process/making denser" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case deep thought process/making denser = concentration.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 CONCENTRATION mean?
CONCENTRATION noun- The act, process or ability of concentrating; the process of becoming concentrated, or the state of being concentrated.
- A field or course of study on which one focuses, especially as a student in a college or university.
- The proportion of a substance in a whole.
- The matching game pelmanism.