fight

from The American Heritage® Dictionary of the English Language, 5th Edition.

• intransitive verb To attempt to harm or gain power over an adversary by blows or with weapons.
• intransitive verb Sports To engage in a boxing match.
• intransitive verb To engage in a quarrel; argue.
• intransitive verb To strive vigorously and resolutely, as in trying to overcome something; contend: synonym: oppose.
• intransitive verb To contend with or oppose with violence or in battle.
• intransitive verb To wage or carry on (a battle).
• intransitive verb To contend for, as by combat.
• intransitive verb Sports To box against (an opponent).
• intransitive verb To participate in (a boxing match or other similar contest).
• intransitive verb To cause (a boxer or other contestant) to fight in a match.
• intransitive verb To contend with or struggle against.
• intransitive verb To try to prevent the development or success of.
• intransitive verb To try to extinguish (an uncontrolled fire).
• intransitive verb To make (one's way) by struggle or striving.
• noun A confrontation between opposing groups in which each attempts to harm or gain power over the other, as with bodily force or weapons.
• noun A physical conflict between two or more individuals.
• noun Sports A boxing match.
• noun A quarrel or conflict.
• noun A struggle to achieve an objective.
• noun The power or inclination to fight; pugnacity.
• idiom (fight fire with fire) To combat one evil or one set of negative circumstances by reacting in kind.
• idiom (fight shy of) To avoid meeting or confronting.

from The Century Dictionary.

• To engage in battle or in single combat; contend in arms; attempt to defeat, subdue, or destroy an adversary by physical means.
• To contend in any way; struggle for the gaining of an end; strive vigorously: as, to fight against disease; to fight in a political campaign.
• To contend with in battle; war against: as, they fought the enemy in two pitched battles.
• To contend against in any manner.
• To carry on or wage, as a battle or other contest.
• To win or gain by battle or contest of any kind; sustain by fighting.
• To cause to fight; manage or manœuver in a fight: as, to fight cocks; to fight one's ship.
• noun A battle; an attempt to overcome or defeat by physical means; a contest with natural or other weapons.
• noun Any contest or struggle.
• noun A bulkhead or other screen designed for the protection of the men during a battle; a bulwark. See close-fights.
• noun Power or inclination for fighting.
• noun Synonyms Conflict, Combat, etc. (see battle); fray, affray, encounter, affair, brush.

from the GNU version of the Collaborative International Dictionary of English.

• intransitive verb To strive or contened for victory, with armies or in single combat; to attempt to defeat, subdue, or destroy an enemy, either by blows or weapons; to contend in arms; -- followed by with or against.
• intransitive verb To act in opposition to anything; to struggle against; to contend; to strive; to make resistance.
• intransitive verb to avoid meeting fairly or at close quarters; to keep out of reach.
• noun A battle; an engagement; a contest in arms; a combat; a violent conflict or struggle for victory, between individuals or between armies, ships, or navies, etc.
• noun A struggle or contest of any kind.
• noun colloq. Strength or disposition for fighting; pugnacity.
• noun obsolete A screen for the combatants in ships.
• noun a fight in which the enemy is continually chased; also, one which continues without definite end or result.
• transitive verb To carry on, or wage, as a conflict, or battle; to win or gain by struggle, as one's way; to sustain by fighting, as a cause.