What is the meaning of node?

noun

• A connecting point at which several lines come together.
• Any thickened enlargement.
  • synonyms: knob, thickening
• Botany) the small swelling that is the part of a plant stem from which one or more leaves emerge.
  • synonyms: leaf node
• Physics) the point of minimum displacement in a periodic system. (
• Astronomy) a point where an orbit crosses a plane. (
• The source of lymph and lymphocytes.
  • synonyms: lymph node, lymph gland
• Any bulge or swelling of an anatomical structure or part.
• Computer science. ( any computer that is hooked up to a computer network).
  • synonyms: client, guest