Merriam-Webster Collegiate Dictionary - node

 noun  Etymology: Middle English, from Latin nodus knot, ~; akin to Middle Irish naidm bond  Date: 15th century  1.  a. a pathological swelling or enlargement (as of a rheumatic joint)  b. a discrete mass of one kind of tissue enclosed in tissue of a different kind  2. an entangling complication (as in a drama) ; predicament  3. either of the two points where the orbit of a planet or comet intersects the ecliptic; also either of the points at which the orbit of an earth satellite crosses the plane of the equator  4.  a. a point, line, or surface of a vibrating body or system that is free or relatively free from vibratory motion  b. a point at which a wave has an amplitude of zero  5.  a. a point at which subsidiary parts originate or center  b. a point on a stem at which a leaf or leaves are inserted  c. a point at which a curve intersects itself in such a manner that the branches have different tangents  d. vertex 1b