What is light blue; grayish blue; -- a term applied to different shades at different periods. -- n. A cloth of sky-blue color. [Obs.] "A long surcoat of pers." Chaucer called?

pers — Light blue; grayish blue; -- a term applied to different shades at different periods. -- n. A cloth of sky-blue color. [Obs.] "A long surcoat of pers." Chaucer. (Webster's 1913.)