In general, a node is a localized swelling (a "knot") or a point of intersection (a vertex).

Node may refer to:

• Vertex (graph theory), a vertex in a mathematical graph
• Vertex (geometry), 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

• node, the points where a great circle crosses a plane of reference, or the equator of a sphare

• 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

• 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 and atrioventricular node, 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 where a leaf is attached
• In cladistics, a shared ancestor (also see Clade)

• 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 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

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

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

• 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

• 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

• 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

• Nodal (disambiguation)
• Nodule (disambiguation)