Majčin brat je daidža, njegova žena je daidžinica (ujna), njegov sin je daidžić, a kćer daidžićna.

http://www.inantro.hr/admin/_upload/_files/cscamphppei/Bosan...

Your uncle's son will simply be your first cousin (no times removed), more normally just called a cousin.

http://www.blurtit.com/q684702.html

Maternal/paternal cousin
A term that specifies whether the individual is one's cousin on the mother's side (maternal) or father's side (paternal).

http://en.wikipedia.org/wiki/Cousin#Additional_terms

maternal cousin (plural maternal cousins)

1. A child of one's mother's sibling
2. A more distant relative of one's mother who is not a direct ancestor

http://en.wiktionary.org/wiki/maternal_cousin