1. A knob, knot, protuberance, or swelling. 2. The point on a stem where a leaf is attached or has been attached; a joint. 3. A point or region of virtually zero amplitude in a periodic system. 4. The point at which a continuous curve crosses itself. 5. A terminal in a computer network. 6. Either of two diametrically opposite points at which the orbit of a planet intersects the ecliptic. 7. Either of two points at which the orbit of a satellite intersects the orbital plane of a planet.
