An Etymological Dictionary of Astronomy and Astrophysics

Meteorology: A period of several successive days of abnormally hot and usually humid weather occurring in summer.

Etymology (EN): → heat; → wave.

Etymology (PE): Celle-ye tâbestân literally “the fortieth of summer,” i.e. “midsummer,” from cellé pertaining to “forty (days),” from cel, cehel, → forty, + tâbestân, → summer.