An Etymological Dictionary of Astronomy and Astrophysics

1. A point of zero → amplitude in a system of → stationary waves. See also → antinode.
   

2. A → junction point in a network.
   

3. Same as → orbital node; see also → lunar node.
   

4. In → graph theory, same as → vertex.

Etymology (EN): From L. nodus “knot;” cognate with necto “I bind,” Skt. nahyati “binds, ties,” Av. naska-, “bundle,” Old Irish nascim “to bind,” Old Norse knutr, Norwegian knut, Icelandic hnutur, O.E. cnotta, Modern E. knot, O.H.G. knotto, Ger. Knoten; PIE root *ned- “to bind, tie.”

Etymology (PE): Gereh “knot,” from Mid.Pers. grih “knot;” Sogdian γr’nš “knot, bond, joining;” Khotanese grantha- “knot;” cf. Skt. granthi- “knot.”