JEALOUSY, originally a condition of zealous emulation, hence the modern sense of resentment at being supplanted in the affection of another. The word is another form of "zealous," and is derived from Gr. ''CiXos, ardour, from 4ft.v, to boil, ferment. A.
thick, ribbed and non-transparent glass was formerly called "jeal ous-glass"; cf. the borrowed French word jalousie, a blind or shutter, made of slats of wood, which slope in such a way as to admit air and a certain amount of light.