n.
a hostile meeting of opposing military forces in the course of a war; "Grant won a decisive victory in the battle of Chickamauga"; "he lost his romantic ideas about war when he got into a real engagement"
n.
an open clash between two opposing groups (or individuals); "the harder the conflict the more glorious the triumph"--Thomas Paine; "police tried to control the battle between the pro- and anti-abortion mobs"
n.
a course of reasoning aimed at demonstrating a truth or falsehood; the methodical process of logical reasoning; "I can't follow your line of reasoning"