branch

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

• noun A secondary woody stem or limb growing from the trunk or main stem of a tree or shrub or from another secondary limb.
• noun A lateral division or subdivision of certain other plant parts, such as a root or flower cluster.
• noun Something that resembles a branch of a tree, as in form or function, as.
• noun A secondary outgrowth or subdivision of a main axis, such as the tine of a deer's antlers.
• noun Anatomy An offshoot or a division of the main portion of a structure, especially that of a nerve, blood vessel, or lymphatic vessel; a ramus.
• noun A limited part of a larger or more complex unit or system, especially.
• noun An area of specialized skill or knowledge, especially academic or vocational, that is related to but separate from other areas.
• noun A division of a business or other organization.
• noun A division of a family, categorized by descent from a particular ancestor.
• noun Linguistics A subdivision of a family of languages, such as the Germanic branch of Indo-European.
• noun A tributary of a river.
• noun A divergent section of a river, especially near the mouth.
• noun Mathematics A part of a curve that is separated, as by discontinuities or extreme points.
• noun A sequence of program instructions to which the normal sequence of instructions relinquishes control, depending on the value of certain variables.
• noun The instructions executed as the result of such a passing of control.
• noun Chemistry A bifurcation in a linear chain of atoms, especially in an organic molecule where isomeric hydrocarbon groups can vary in the location and number of these bifurcations of the carbon chain.
• intransitive verb To put forth a branch or branches; spread by dividing.
• intransitive verb To come forth as a branch or subdivision; develop or diverge from.
• intransitive verb To enlarge the scope of one's interests, business, or activities.
• intransitive verb Computers To relinquish control to another set of instructions or another routine as a result of the presence of a branch.
• intransitive verb To separate (something) into branches.
• intransitive verb To embroider (something) with a design of foliage or flowers.

from The Century Dictionary.

• noun A division or subdivision of the stem or axis of a tree, shrub, or other plant (the ultimate or smaller ramifications being called branchlets, twigs, or shoots); a bough.
• noun Something resembling a branch in its relation to the trunk; an offshoot or part extending from the main body of a thing; a ramification; a subdivision; an outgrowth.
• noun Specifically— Any member or part of a body or system; a department; a section or subdivision: as, a branch of a society; the various branches of learning.
• noun A line of family descent, in distinction from some other line or lines from the same stock: as, the English or the Irish branch of a family.
• noun Any descendant in such a line.
• noun In geometry, any portion of a real curve capable of description by the continuous motion of a point. Every branch either extends to infinity or returns into itself (reëntrant branch); but some old geometers considered a branch to be ended by a cusp.
• noun A piece of pipe including a length of the main pipe and a shorter piece branching from it. When the latter is at right angles to the former, the branch is aT-branch; if at an acute angle, it is a y-branch. If there are two branching pieces, it is called a double branch.
• noun The metal piece on the end of the hose of a fire-engine to which the nozle is screwed.
• noun One of the sides of a horseshoe.
• noun In fortification, the wing or long side of a horn- or crown-work; also, one of the parts of a zig-zag approach.
• noun In a sword-hilt, either of two pieces which project at right angles to the barrel and to the blade of the sword, forming guards for the hand. See hilt.
• noun In entomology, the flagellum or outer portion of a geniculate antenna.
• noun In mining, a small vein, leader, or string of ore, connected with or seeming to branch from the main lode. See lode.
• noun In a bridle, either of two bent pieces of iron which bear the bit, the cross-chains, and the curb.
• noun In the southern and some of the western United States, the general name for any stream that is not a large river or a bayou.
• noun The diploma or commission issued by the proper authority to a pilot who has passed an examination for competency.
• noun A chandelier.
• noun A branched candlestick or candle.
• Consisting of or constituting a branch; ramifying; diverging from a trunk, main stem, or main body: as, a branch road or railroad; a branch society.
• To spread in branches; send out branches, as a plant.
• To divide into separate parts or subdivisions; diverge; ramify.
• To divide, as into branches; make subordinate divisions in.
• To adorn with needlework; decorate with embroidery; adorn with flowers or other ornament, as in textile fabrics.