median (adj.) Look up median at
1590s, from Middle French médian (15c.) and directly from Latin medianus "of the middle," from medius "in the middle" (see medial (adj.)). Originally anatomical, of veins, arteries, nerves. Median strip "strip between lanes of traffic" is from 1954.
median (n.) Look up median at
"a median part," 1540s, from Latin medianus (see median (adj.)). Meaning "middle number of a series" is from 1883.