In general, a node is a localized swelling (a "

knot A knot is an intentional complication in Rope, cordage which may be practical or decorative, or both. Practical knots are classified by function, including List of hitch knots, hitches, List of bend knots, bends, List of loop knots, loop knots, ...

") or a point of intersection (a vertex). Node may refer to:

In mathematics

* Vertex (graph theory), a vertex in a mathematical graph *

Vertex (geometry) In geometry, a vertex (: vertices or vertexes), also called a corner, is a point (geometry), point where two or more curves, line (geometry), lines, or line segments Tangency, meet or Intersection (geometry), intersect. For example, the point wh ...

, a point where two or more curves, lines, or edges meet. * Node (autonomous system), behaviour for an ordinary differential equation near a critical point * Singular point of an algebraic variety, a type of singular point of a curve

In science and engineering

Spherical geometry

* node, the points where a great circle crosses a plane of reference, or the equator of a sphere

Astronomy

* Orbital node, the points where an orbit crosses a plane of reference ** Lunar node, where the orbits of the Sun and Moon intersect ** Longitude of the ascending node, how orbital nodes are parameterized

Biology

* Lymph node, an immune system organ used to store white blood cells * Node of Ranvier, periodic gaps in the insulating myelin sheaths of myelinated axons *

Sinoatrial node The sinoatrial node (also known as the sinuatrial node, SA node, sinus node or Keith–Flack node) is an ellipse, oval shaped region of special cardiac muscle in the upper back wall of the right atrium made up of Cell (biology), cells known as pa ...

and

atrioventricular node The atrioventricular node (AV node, or Aschoff-Tawara node) electrically connects the heart's atria and ventricles to coordinate beating in the top of the heart; it is part of the electrical conduction system of the heart. The AV node lies at the ...

, specialized tissues in the heart responsible for initiating and coordinating the heartbeat * Primitive knot or primitive node, the organizer tissue for gastrulation in vertebrates *The place on a

plant stem A stem is one of two main structural axes of a vascular plant, the other being the root. It supports leaf, leaves, flowers and fruits, transports water and dissolved substances between the roots and the shoots in the xylem and phloem, engages ...

where a leaf is attached *In

cladistics Cladistics ( ; from Ancient Greek 'branch') is an approach to Taxonomy (biology), biological classification in which organisms are categorized in groups ("clades") based on hypotheses of most recent common ancestry. The evidence for hypothesiz ...

, a shared ancestor (also see

Clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

)

Computing and electronics

* Node (networking), a point of connection in a communication network *An entity in a mesh network * Node (circuits), a region in an electrical circuit where there is no change in potential *

Node (computer science) A node is a basic unit of a data structure, such as a linked list or Tree (data structure), tree data structure. Nodes contain data and also may link to other nodes. Links between nodes are often implemented by Pointer (computer programming), point ...

, a basic unit used to build data structures * Goal node (computer science), a node in a graph that meets defined criteria for success or termination * Node (UML), the representation of a computational device in the Unified Modeling Language * Node.js, a JavaScript-based, cross-platform runtime environment * NodeB, hardware that is connected to the mobile phone network * NODE (wireless sensor), a wireless handheld sensor for smart devices *Node, a shorthand used to designate a

semiconductor fabrication process Semiconductor device fabrication is the process used to manufacture semiconductor devices, typically integrated circuits (ICs) such as microprocessors, microcontrollers, and memories (such as Random-access memory, RAM and flash memory). It is a ...

Linguistics

* Node (linguistics), a branch point in the Tree model, or Node Theory, of language evolution

Physics

* Node (physics), a point along a standing wave where the wave has minimal amplitude

Space-station modules

* Unity (ISS module) or Node 1, one of the first modules of the International Space Station * Harmony (ISS module) or Node 2, module of the International Space Station * Tranquility (ISS module) or Node 3, a module of the International Space Station with the Cupola * Node 4, a proposed module of the International Space Station * '' Prichal (ISS module)'', a planned module of the International Space Station to be launched in 2021

In music

* Node (band), Italian death metal band * Node (singer), Danish singer and hip hop artist of Kurdish origin * ''Node'' (album), a 2015 album by Australian metalcore band Northlane

Other uses

* Node, Kentucky * Node tribe, a community of pastoral nomads in India and Pakistan * Node, a transport hub in a transportation system * Giordana Racing Team, a British cycling team, formerly named Node4-Giordana *'' Node Magazine'', a literary project based on the novel '' Spook Country'' by William Gibson *''New Oxford Dictionary of English'', a single-volume English language dictionary, see Oxford Dictionary of English *Node, a cyborg with a donated human face used as a guide, in " Silence in the Library" (''Doctor Who'') *Node, the pommel-like part of a chalice where the stem meets the cup *A nodal organizational structure, such as in terms of business management, see

Cellular organizational structure A non-biological entity with a cellular organizational structure (also known as a cellular organization, cellular system, nodal organization, nodal structure, et cetera) is set up in such a way that it mimics how Natural science, natural systems ...

*Node in aroid plant
What is a node?
A node is a small, brown bump on the stem of an aroid plant. It's the point where leaves and aerial roots grow. Nodes contain meristematic tissue, which is responsible for the growth of new roots and shoots.