Mrk is of Slavic origin, derived from the South Slavic element 'Marko', which means 'dedicated to Mars'. It is a short form of names such as Mark, Marco, or Markus. The name is popular in several Slavic countries, including Croatia and Serbia.
"The name Mrk experienced varying popularity over the years, with peaks in 1957, 1969, and 1985 when there were 8 births each, and a notable rise in 1987 with 9 births. However, it was not consistently favored annually, as evidenced by gaps between registrations in certain years."