početnica

1. (of a woman) beginner; novice
   Ja sam još početnica u jogi. — I'm still a beginner at yoga.
   Za početnicu igra stvarno odlično. — She plays really well for a beginner.
2. Croat. (of a book) primer; first reader
   Prvašići uče slova iz početnice. — First-graders learn the letters from the primer.

The masculine form is početnik. In the sense 'primer' the word is Croatian; in Serbia: bukvar.