conflict

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A state of open, often prolonged fighting; a battle or war.
2. n. A state of disharmony between incompatible or antithetical persons, ideas, or interests; a clash.
3. n. Psychology A psychic struggle, often unconscious, resulting from the opposition or simultaneous functioning of mutually exclusive impulses, desires, or tendencies.
4. n. Opposition between characters or forces in a work of drama or fiction, especially opposition that motivates or shapes the action of the plot.
5. v. To be in or come into opposition; differ.
6. v. Archaic To engage in warfare.

Century Dictionary and Cyclopedia

1. To strike or dash together; meet in opposition; come together violently.
2. To contend; fight; strive; struggle.
3. To be in opposition; be contrary or at variance: as, the evidence given by the second witness conflicted with that given by the first.
4. n. A struggle for mastery; a striving to oppose or overcome; a battle or combat; contention; controversy; strife.
5. n. Discord of action, feeling, or effect; antagonism, as of interests or principles; counteraction, as of causes, laws, or agencies of any kind; opposing action or tendency; opposition; collision: as, a conflict of the elements, or between right and wrong.

Wiktionary

1. n. A clash or disagreement, often violent, between two opposing groups or individuals.
2. n. An incompatibility, as of two things that cannot be simultaneously fulfilled.
3. v. To be at odds (with); to disagree or be incompatible
4. v. To overlap (with), as in a schedule.

GNU Webster's 1913

1. n. A striking or dashing together; violent collision.
2. n. A strife for the mastery; hostile contest; battle; struggle; fighting.
3. v. To strike or dash together; to meet in violent collision; to collide.
4. v. To maintain a conflict; to contend; to engage in strife or opposition; to struggle.
5. v. To be in opposition; to be contradictory.

WordNet 3.0

1. n. a hostile meeting of opposing military forces in the course of a war
2. v. be in conflict
3. v. go against, as of rules and laws
4. n. a state of opposition between persons or ideas or interests
5. n. a disagreement or argument about something important
6. n. an open clash between two opposing groups (or individuals)
7. n. opposition between two simultaneous but incompatible feelings
8. n. an incompatibility of dates or events
9. n. opposition in a work of drama or fiction between characters or forces (especially an opposition that motivates the development of the plot)