(medicine) a small structure in the heart, located in the Koch's triangle, near the coronary sinus on the interatrial septum

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

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

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

Alternative form of antinode