klinjo

1. colloq. affect. kid; little boy
   Ej, klinjo, gde su ti roditelji? — Hey, kid, where are your parents?
   Taj klinjo stalno igra fudbal ispred zgrade. — That kid is always playing football in front of the building.

Often used as an affectionate or joking form of address; klinac or dečak are more neutral.