The most common and most likely answer to this crossword clue is the 9 letter word ARROWROOT
I've seen this crossword clue in Financial Times
A
R
R
O
W
R
O
O
T
More clues leading to the result ARROWROOT
- Plant vegetable, losing miles on regular journey to state
- A right dust-up over source of Carib foodstuff
- A right dispute over Australian native initially truculent in plant
- Source of thickness of Cockney school base?
- Barb exposed argument with England cricketerin West Indian ground
- Jumper on line inside craft plant
- Point to or read up what Victorians put in puddings
- It points to the bottom of the plant
- Plant weapon to gain privileged control
- Plant weapon base
Buddy explains!

The straight part
We know that "Carib foodstuff" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case carib foodstuff = arrowroot.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 ARROWROOT mean?
ARROWROOT noun- Maranta arundinacea from the Marantaceae family, a large perennial herb native to the Caribbean area with green leaves about 15 centimeters long.
- Usually preceded by an attributive word: some other plant the rhizomes of which are used to prepare a substance similar to arrowroot (sense 3), such as Zamia integrifolia (Florida arrowroot) or Pueraria montana var. lobata (Japanese arrowroot or kudzu).
- A starchy substance obtained from the rhizomes of an arrowroot plant used as a thickener.