polemic

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A controversial argument, especially one refuting or attacking a specific opinion or doctrine.
2. n. A person engaged in or inclined to controversy, argument, or refutation.
3. adj. Of or relating to a controversy, argument, or refutation.

Century Dictionary and Cyclopedia

1. Of or pertaining to controversy; controversial; disputative: as, a polemic essay or treatise; polemic divinity or theoIogy; polemic writers.
2. n. A disputant; one who carries on a controversy; a controversialist; one who writes in support of an opinion or a system in opposition to another.
3. n. A controversy; a controversial argument.

Wiktionary

1. n. A person who writes in support of one opinion, doctrine, or system, in opposition to another; one skilled in polemics; a controversialist; a disputant.
2. n. An argument or controversy.
3. n. ​ A strong verbal or written attack on someone or something.
4. adj. Having the characteristics of a polemic.

GNU Webster's 1913

1. adj. Of or pertaining to controversy; maintaining, or involving, controversy; controversial; disputative.
2. adj. Engaged in, or addicted to, polemics, or to controversy; disputations.
3. n. One who writes in support of one opinion, doctrine, or system, in opposition to another; one skilled in polemics; a controversialist; a disputant.
4. n. A polemic argument or controversy.

WordNet 3.0

1. adj. of or involving dispute or controversy
2. n. a writer who argues in opposition to others (especially in theology)
3. n. a controversy (especially over a belief or dogma)