Conflict involving close contact between big Japanese corporations (4)

I believe the answer is:

sumo

I'm a little stuck... Click here to teach me more about this clue!

'conflict' is the definition.
Both the answer and definition are singular nouns.
Maybe there's an association between them I don't understand?

I don't understand the rest of the clue.

Can you help me to learn more?

(Other definitions for sumo that I've seen before include "Japanese wrestling for huge men" , "Grappling" , "Jap. wrestling" , "Style of traditional Japanese wrestling" , "Japanese wrestling with big fat men" .)

I've seen this clue in The Independent.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.