Omaima
Yes. It is a classical Arabic diminutive of 'Umm' and appears in Arabic onomastic records and biographical lists.
No. The name does not appear in the Quran, though it is used in historical Muslim sources.
Linguistically it is the diminutive of 'Umm' (mother), giving the sense 'little mother' or an affectionate 'nurturer'.
Variants such as Umayma/Umaymah are recorded among women in early Islamic biographical works and later genealogies; the exact individuals differ across sources.
In Arabic it is pronounced [ʔuˈmajma], commonly transliterated as Omaima or Umayma; stress on the second syllable.