Debatable
Part of speech: adjective
Definition: Controversial. Not fully proved, open to debate, sometimes used humorously. Of a person, argumentative. A fitting subject for debate.
Example sentence: It was a fair decision, the penalty, even though it was debatable whether it was inside or outside the box.
Disputable
Part of speech: adjective
Definition: Of opinions, propositions or questions, subject to dispute; not settled.