Entomology definition of Discal cell: Lepidoptera; the large or median cell
extending from the base of the wing toward the center: = radial
cell (Comst.): in Diptera (Will.) = 1st medial 2 (Comst.):
Odonata; = discoidal areolets, q.v.: Trichoptera, the cell
between the forks of the radial sector, and separated from the 2d
apical cell by a cross-vein.