Nadia is a female name, that is used predominantly throughout the Mediterranean region, Eastern Europe, Latin America, the Caucasus, and the Arab world. Its origins are in the Slavic languages. Variations include Nadja, Nadya, Nadine, Nadiya, and Nadiia.

The names similar to Nadia mean "hope" in many Slavic languages: Ukrainian Nadiya (Надія, accent on the i), Belarusian Nadzeya (Надзея, accent on the e), and Old Polish Nadzieja, all of which are derived from Proto-Slavic *naděja, the first three from Old East Slavic. In Bulgarian and Russian, on the other hand, Nadia or Nadya (Надя, accent on first syllable) is the diminutive form of the full name Nadyezhda (Надежда), meaning "hope" and derived from Old Church Slavonic, which it entered as a translation of the Greek word ἐλπίς (Elpis), with the same meaning.
 
In Arabic, Nadiyyah means "tender" and "delicate." It is derived from the name Nada which means “dew” ( ندى ).

In Russian military aircraft, the voice warning system is given the name Nadia.
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