An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

1) A very harsh, bright, dazzling light.
2) A type of → light pollution which is a blinding light within the field of vision. It compromises security and safety.

M.E. glaren; cognate with M.Du., M.L.G. glaren; akin to glass.

Xirtâv, literally "dazzling light," from xir, from xiré konandé, "dazzling," from xiré "much, many; obstinate; perverse; unwilling;" + tâv, variant tâb, tâbidan "to shine," → luminous.