1206, from O.N.Fr. planke (O.Fr. planche) "plank, slab, little wooden bridge," from L.L. planca "broad slab, board," related to phalanga "pole to carry burdens," from Gk. phalange (see
phalanx). Technically, timber sawed to measure 2 to 6 inches thick, 9 inches or more wide,