The most common and most likely answer to this crossword clue is the 7 letter word MADDEST
I've seen this crossword clue in The Daily Telegraph
M
A
D
D
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More clues leading to the result MADDEST
Buddy explains!
The straight part
We know that "Having grown most bananas" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case having grown most bananas = maddest.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 MADDEST mean?
MADDEST adjective- Insane; crazy, mentally deranged.
- (chiefly US; informal in UK) Angry, annoyed.
- Bizarre; incredible.
- Wildly confused or excited.
- Extremely foolish or unwise; irrational; imprudent.
- (usually with for or about) Extremely enthusiastic about; crazy about; infatuated with; overcome with desire for.
- (of animals) Abnormally ferocious or furious; or, rabid, affected with rabies.
- (chiefly Northeastern US) Intensifier, signifies an abundance or high quality of a thing; very, much or many.
- (of a compass needle) Having impaired polarity.