(astronomy) The point in an orbit at which a body passes the ecliptic plane going north.

plural of ascending node

(oceanography) A region of the ocean which experiences little to no tidal fluctuation.

plural of tidal node

plural of Osler node

A painful, red, raised skin lesion, usually on the pads of the fingers or toes, indicative of the heart disease bacterial endocarditis.

plural of lymph node

(anatomy, immunology) Synonym of lymph node.

plural of lymphatic node

(anatomy, immunology) Each of the small oval bodies of the lymphatic system, distributed along the lymphatic vessels, that are clustered in the armpits, groin, neck, chest and abdomen. They act as filters, with an internal honeycomb of connective tissue filled with lymphocytes and macrophages that collect and destroy bacteria, viruses and foreign matter from lymph. When the body is fighting an infection, these lymphocytes multiply rapidly and produce a characteristic swelling of the lymph nodes.