Female:
Glikeriya is the Russian form of the Greek name Glykeria, derived from root glykys (sweet).
Gordana means “dignified” in Macedonian, Serbian, and Croatian. The male form is Gordan. Both were popularised by the 1935 novel Gordana, by Croatian writer Marija Jurić Zagorka.
Grażyna is a Polish name derived from the Lithuanian word for “beautiful.” It was invented by great national poet Adam Mickiewicz in an 1823 poem of the same name.
Grozdana, Grozda means “grapes” in Bulgarian and Macedonian. The male form is Grozdan.
Gvozdana means “iron-like” in Serbian and Croatian. The male form is Gzovden.
Gvozdika means “carnation” in Russian. This was one of the newly-created Soviet names, used by parents eager to reject traditional names. It refers to the red carnation, a symbol of both the February and October Revolutions.
Male:
Geberyk is the Polish form of the Ancient Germanic name Geberic, Gabaric, derived from Gothic roots giban (to give) and rîcja (strong, powerful, mighty). The second root also has cognates in Gothic reiks and Celtic rix and rîg, which all mean “king, ruler.”
Gennadiy (Russian) and Genadiy (Bulgarian) are forms of the Greek name Gennadios (generous, noble). The nicknames are Genna, Gena, and Genya. A less common feminine form is Gennadiya.
Genseryk is the Polish form of Ancient Germanic name Geiseric, Gaiseric (powerful spear). Geiseric the Lame was a fifth century king of the Vandals and Alans.
Gerasim (Russian, Bulgarian, Macedonian) and Gerazym (Polish) are forms of the Greek name Gerasimos, derived from root geras (gift, honour). I have a priest character named Father Gerasim.
Gleb is the Russian and Ukrainian form of the Old Norse name Guðleifr (good heir). Though most classic Russian names are of Slavic or Greek origin, there are a few Old Norse ones bearing testament to their ancient history and how the first of their two dynasties was founded by a Varangian (Viking) prince.
Goran means “mountain man” in Serbian, Macedonian, Bulgarian, Slovenian, and Croatian, from root gora (mountain). It became popular thanks to Croatian poet Ivan Goran Kovačić, whose middle name came from the mountain town where he was born. The feminine form is Goranka.
Onomastics Outside the Box 
I think Glikeriya is a very interesting name, and so is the Polish Gliceria. It sounds a bit like glycerine to me, but is still kind of cool, I like the sound anyway. I can say that Grażyna was fairly popular from like late 1950’s to early 1970’s in Poland, so when I think of it I definitely see a woman in her 40’s-early 50’s.
Great resource for anyone writing Slavic fiction and wanting the names to be authentic
Debbie
Goran – liked the name ever since I watched Goran Ivanesavic play tennis. [Excuse my spelling.]
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