/kawr"dn/ , n.
1. a line of police, sentinels, military posts, warships, etc., enclosing or guarding an area.
2. a cord or braid worn for ornament or as a fastening.
3. a ribbon worn usually diagonally across the breast as a badge of a knightly or honorary order.
4. Fort.
a. a projecting course of stones at the base of a parapet.
b. the coping of a scarp.
5. Archit.
a. a stringcourse, esp. one having little or no projection.
b. a cut-stone riser on a stepped ramp or the like.
6. a fruit tree or shrub trained to grow along a support or a series of such supports.
v.t.
7. to surround or blockade with or as with a cordon (usually fol. by off ): The police cordoned off the street.
[ 1400-50; ME corde ]