me·di·an 
(mēdē-ən)
(mēdē-ən)adj.
1. Relating to, located in, or extending toward the middle.
2. Anatomy Of, relating to, or situated in or near the plane that divides a bilaterally symmetrical animal into right and left halves; mesial.
3. Statistics Relating to or constituting the middle value in a distribution.
n.
1. A median point, plane, line, or part.
2. The dividing area, either paved or landscaped, between opposing lanes of traffic on some highways. Also called regionally boulevard, mall, median strip, meridian, neutral ground.
3. Statistics The middle value in a distribution, above and below which lie an equal number of values.
4. Mathematics
a. A line that joins a vertex of a triangle to the midpoint of the opposite side.
b. The line that joins the midpoints of the nonparallel sides of a trapezoid.
[Latin mediānus, from medius, middle; see medhyo- in the Appendix of Indo-European roots.]
medi·an·ly adv.
median
mediantop:three medians of a triangle and the median of a trapezoid
bottom: highway median