1) Arguable 2) Contentious 3) Debatable 4) Disputable 5) Disputatious 6) Disputed 7) Given to controversy 8) Litigious 9) Moot 10) Polemic 11) Polemical 12) Subject to controversy 13) Touchy 1) Arguable 2) Debatable 3) Disputed 4) Edgy 5) Eristic 6) Eristical 7) Polemic 8) Polemical 9) Sensitive 
• (a.) Relating to, or consisting of, controversy; disputatious; polemical; as, controversial divinity.
[Adjective] Something that people are likely to disagree or argue about.
Con`tro·ver'sial adjective [ Confer Late Latin controversialis .] Relating to, or consisting of, controversy; disputatious; polemical; as, controversial divinity. « Whole libraries of controversial books. Macaulay. » 
[adj] - marked by or capable of arousing controversy
causing much disagreement or debate
adjective marked by or capable of arousing controversy; `the issue of the death penalty is highly controversial`; `Rushdie`s controversial book`; `a controversial decision on affirmative action`
of, pertaining to, or characteristic of controversy; polemical: a controversial book. · subject to controversy; debatable: a controversial decision. · given to controversy; disputatious.
[SAT terms] marked by or capable of arousing disagreement marked by or capable of arousing disagreement