The most common and most likely answer to this crossword clue is the 8 letter word RUTABAGA
R
U
T
A
B
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G
A
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The straight part
We know that "vegetable" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case vegetable = rutabaga.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 RUTABAGA mean?
RUTABAGA noun- The swede, or Swedish turnip; the European plant Brassica napus var. napobrassica
- The edible root of this plant