The most common and most likely answer to this crossword clue is the 9 letter word ETIOLATED
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The straight part
We know that "went pale" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case went pale = etiolated.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 ETIOLATED mean?
ETIOLATED adjective- Of a plant or part of a plant: pale and weak because of sunlight deprivation or excessive exposure to sunlight.
- Of a plant: intentionally grown in the dark.
- (by extension) Of an animal or person: having an ashen or pale appearance; also, haggard or thin; physically weak.
- Lacking in vigour; anemic, feeble.
- To make pale through lack of light, especially of a plant.
- To make pale and sickly-looking.
- To become pale or blanched.