node

1. A knot, knob, protuberance or swelling.
2. The point where the orbit of a planet, as viewed from the Sun, intersects the ecliptic. The ascending and descending nodes refer respectively to the points where the planet moves from South to North and N to S; their respective symbols are ☊ and ☋.
3. A leaf node.
4. A computer or other device attached to a network.
5. The point at which the lines of a funicular machine meet from different angular directions.
6. The point at which a curve crosses itself, being a double point of the curve. See crunode and acnode.
7. A similar point on a surface, where there is more than one tangent-plane.
8. A vertex or a leaf in a graph of a network, or other element in a data structure.

Plural nodes