n. 1 Bot. a the part of a plant stem from which one or more leaves emerge. b a knob on a root or branch. 2 Anat. a natural swelling or bulge in an organ or part of the body. 3 Astron. either of two points at which a planet's orbit intersects the plane of the ecliptic or the celestial equator. 4 Physics a point of minimum disturbance in a standing wave system. 5 Electr. a point of zero current or voltage. 6 Math. a a point at which a curve intersects itself. b a vertex in a graph. 7 a component in a computer network. nodal adj. nodical adj. (in sense 3).
[ L nodus knot ]