different between debatable vs contestability

English

From Old French debatable (French débattable).

debatable (comparative more debatable, superlative most debatable)

Open to debate; not fully proved or confirmed.
Those data are debatable: no one has been able to replicate them.
It's debatable whether he is the best candidate for the position.
Able to be debated; up for discussion.
The lack of bonuses this year is not debatable.

debatable (plural debatables)

A topic that is open to debate.
- 1988, Ray Barr, 1,001 medical facts for every home (page 314)
  Just how many glaucoma patients there are in the United States and just how prevalent is the disease are two unknowns or at least two debatables.

contest +? -ability

contestability (uncountable)

The property of being contestable or debatable.
Because of the popularity of the sitting candidate, the contestability of the seat was poor.

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