The most common and most likely answer to this crossword clue is the 6 letter word CITRUS
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The straight part
We know that "Orange, say" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case orange, say = citrus.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 CITRUS mean?
CITRUS noun- Any of several shrubs or trees of the genus Citrus in the family Rutaceae.
- The fruit of such plants, generally spherical, oblate, or prolate, consisting of an outer glandular skin (called zest), an inner white skin (called pith or albedo), and generally between 8 and 16 sectors filled with pulp consisting of cells with one end attached to the inner skin. Citrus fruits include orange, grapefruit, lemon, lime, and citron.
- Of or relating to citrus plants or fruit.