The most common and most likely answer to this crossword clue is the 9 letter word EAGERNESS
I've seen this crossword clue in The Times
E
A
G
E
R
N
E
S
S
More clues leading to the result EAGERNESS
- Green seas generated enthusiasm
- About time birds of prey start to show enthusiasm
- Keen nature of silver eagles in European sierra
- Sees anger transforming into anxiety
- School agree head’s showing great enthusiasm
- Sense rage damaged enthusiasm
- Agree new head shows enthusiasm
- Ardour‘s small on grand bird in endless repose
- Cook sees range with enthusiasm
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The straight part
We know that "anxiety" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case anxiety = eagerness.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 EAGERNESS mean?
EAGERNESS noun- The state or quality of being eager; ardent desire.
- Tartness; sourness