The most common and most likely answer to this crossword clue is the 8 letter word TWINKLED
I've seen this crossword clue in The Guardian
T
W
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D
Buddy explains!
The straight part
We know that "smiled with her eyes" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case smiled with her eyes = twinkled.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 TWINKLED mean?
TWINKLED verb- (of a source of light) to shine with a flickering light; to glimmer
- (chiefly of eyes) to be bright with delight
- To bat, blink or wink the eyes
- To flit to and fro