Male:
Jaagup is a form of Jakob (heel).
Jaroslav is borrowed from Russian name Yaroslav, and means “fierce and glorious.” This is a fairly popular name.
Joonas is the Estonian form of Jonah (dove).
Juhan is the Estonian form of John (God is gracious).
Jukk seems to be a nickname for Juhan.
Jürgo is a form of George (farmer).
Female:
Janeli is a fairly popular name I couldn’t find the etymology of.
Janika is a very popular form of Jane, also used in Finnish.
Jaune means “young.”
Jolanta is borrowed from Latvian, and derives from Yolanda, which may mean “violet.”
Julve is an Estonian form of Julia.
Juta is a form of Judith.
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