box pleat
noun
1.
a double pleat, with the material folded under at each side.
Also called
box plait
.
Origin
1880-85
Examples from the web for
box pleat
They shall be cut square at the bottom and have a one and one-half inch
box pleat
in the center.
The back is trimmed with a
box pleat
on each side and is fastened by three tiny buttons.
British Dictionary definitions for
box pleat
box pleat
noun
1.
a flat double pleat made by folding under the fabric on either side of it