It is the root of the names Kovačević, Kovačić, Kowalski, Kowalchuk, Kowalczyk, Kovachev, Kovalenko, Kovalyov, and Kovalev.
The given name Petr, Petro, Pyotr or Petar (equivalent to Peter) can become Petrov, Petriv, Petriw, Petrenko, Petrovsky, Petrović, Petrić, Petrič, Petrich, etc.
In East Slavic languages (Belarusian, Russian, Rusyn, and Ukrainian) the same system of name suffixes can be used to express several meanings.
Similarly, many suffixes can be attached to express affection or informality (in linguistics, called a diminutive).
For example, calling a boy named Ivan "Ivanko", "Ivo", "Ivica" etc, or Yuri "Yurko", expresses that he is familiar to you.