The most common and most likely answer to this crossword clue is the 8 letter word FUGACITY
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The straight part
We know that "Inclination to escape" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case inclination to escape = fugacity.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 FUGACITY mean?
FUGACITY noun- A measure of the tendency of a fluid to expand or escape.
- A measure of the relative stability of different phases of a substance under the same conditions.
- Transience.