I've heard this name used (so the spelling might not be correct, though I hope it is) on a Muslim woman, and I'm guessing it's probably a relative of Esther, or Ishtar. Does anyone know which language this name comes from?
"A Dictionary of Muslim Names" by Salahuddin Ahmed includes the female name Izdihar, which is said to mean "prosperity, flourishing, bloom" in Arabic. Perhaps that is what you heard.