Examples from the Web for discal
The male never has a costal fold on the fore wings, and but rarely is provided with a discal stigma.
Wings long, with the discal areolets from the base to beyond the middle mostly vitreous, but having the veins bordered with brown.
The discal band of spots common to both wings is broken and irregular, and the spots on the hind wings are quite small.
Discal area: of a wing applies especially to the more central portion, or that area covered by the discal cell.
Discal: on or relating to the disc of any surface or structure.