median

1. (anatomy, now rare) A central vein or nerve, especially the median vein or median nerve running through the forearm and arm.Examples: "Why is not our jugular or throat-veine as much at our command as the mediane [translating mediane]?"; "The Greeks prescribe the median or middle vein to be opened, and so much blood to be taken away as the patient may well spare, and the cut that is made must be wide enough."archaic

2. (geometry) A line segment joining the vertex of triangle to the midpoint of the opposing side.

3. (statistics) A number separating the higher half from the lower half of a data sample, population, or probability distribution. The median of a finite list of numbers can be found by arranging all the observations from lowest value to highest value and picking the middle one (e.g., the median of {3, 3, 5, 9, 11} is 5). If there is an even number of observations, then there is no single middle value; the median is then usually defined to be the mean of the two middle values.

4. (US) The area separating two lanes of opposite-direction traffic.Examples: "Seen from street level, the median was clean most days. From the third floor you peered over the benches and trees and saw the trash crowding the subway ventilation grates and paving stones."Synonyms: median strip, central reservation, reservationUS