The most common and most likely answer to this crossword clue is the 7 letter word GAMBOGE
I've seen this crossword clue in The Times
G
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More clues leading to the result GAMBOGE
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The straight part
We know that "yellow" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case yellow = gamboge.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 GAMBOGE mean?
GAMBOGE noun- One of several species of trees of the genus Garcinia found in South and Southeastern Asia, especially Garcinia xanthochymus.
- The resin of the gamboge tree; a preparation of the resin used as a pigment or for medicinal purposes.
- A deep yellow colour.
- Of a deep yellow colour.