divide

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

• intransitive verb To separate into parts, sections, groups, or branches: synonym: separate.
• intransitive verb To form a border or barrier between.
• intransitive verb To sector into units of measurement; graduate.
• intransitive verb To group according to kind; classify or assign.
• intransitive verb To cause to separate into opposing factions; disunite.
• intransitive verb To cause (members of a parliament) to vote by separating into groups, as pro and con.
• intransitive verb To give out or apportion among a number: synonym: distribute.
• intransitive verb To subject (a number) to the process of division.
• intransitive verb To be a divisor of.
• intransitive verb To use (a number) as a divisor.
• intransitive verb To become separated into parts.
• intransitive verb To branch out, as a river or a blood vessel.
• intransitive verb To form into factions; take sides.
• intransitive verb To vote by dividing.
• intransitive verb Mathematics To perform the operation of division.
• intransitive verb Biology To undergo cell division.
• noun A dividing point or line.

from The Century Dictionary.

• noun In physical geography, a water-shed; the height of land which separates one drainage-basin or area of catchment from another; often, but not always, a ridge or conspicuous elevation.
• noun The act of dividing; a division or partition, as of winnings or gains of any kind: as, a fair divide.
• In billiards, to divide balls (mentally) into sixteenths, eighths, quarters, halves, and three quarters of their diameters, in order to insure certain deviations.
• To separate into parts or pieces; sunder, as a whole into parts; cleave: as, to divide an apple.
• To separate; disjoin; dispart; sever the union or connection of, as things joined in any way, or made up of separate parts: as, to divide soul and body; to divide an army.
• In mathematics: To perform the operation of division on.
• To be a divisor of, without leaving a remainder: as, “7 divides 21.”
• To cause to be separate; part by any means of disjunction, real or imaginary; make or keep distinct: as, the equator divides the earth into two hemispheres.
• To make partition of; distribute; share: as, to divide profits among shareholders, between partners, or with workmen.
• To mark off into parts; make divisions on; graduate: as, to divide a sextant, a rule, etc.
• To disunite or cause to disagree in opinion or interest; make discordant.
• To embarrass by indecision; cause to hesitate or fluctuate between different motives or opinions.
• In music, to perform, as a melody, especially with variations or divisions.
• In logic: To separate (in thought or speech) into parts any of the kinds of whole recognized by logic: as, to divide a conception into its elements (species into genus and difference), an essential whole into matter and form, or an integral whole into its integrate parts.
• Especially, to separate (a genus) into its species.
• To expound; explain.
• Synonyms To sever, sunder, bar apart, divorce.
• To allot, apportion, deal out, parcel out.
• To become separated into parts; come or go apart; be disunited.
• To vote by division. See division, 1 .
• To come to an issue; agree as to what are the precise points in dispute, or some of them.

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

• intransitive verb To be separated; to part; to open; to go asunder.
• intransitive verb To cause separation; to disunite.
• intransitive verb To break friendship; to fall out.
• intransitive verb To have a share; to partake.
• intransitive verb To vote, as in the British Parliament, by the members separating themselves into two parties (as on opposite sides of the hall or in opposite lobbies), that is, the ayes dividing from the noes.
• noun A dividing ridge of land between the tributaries of two streams; also called watershed and water parting. A divide on either side of which the waters drain into two different oceans is called a continental divide.
• transitive verb To part asunder (a whole); to sever into two or more parts or pieces; to sunder; to separate into parts.