contention (DISAGREEMENT) noun [U] the disagreement that results from opposing arguments 
There's a lot of contention about that issue - for every person firmly in favour
 there's someone fiercely against it.
And that very decisive defeat puts them out of contention for this year's championship finals.

contentious adjective 
Contentious means causing or likely to cause disagreement. 
She has some rather contentious views on education.

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