-nik

The English suffix -nik is of Slavic origin. It approximately corresponds to the suffix "-er" and nearly always denotes an agent noun (that is, it describes a person related to the thing, state, habit, or action described by the word to which the suffix is attached). In the cases where a native English language coinage may occur, the "-nik"-word often bears an ironic connotation, as in the case of the terms coined for the failed rocket launch of the U.S. satellite rival to Sputnik, such as kaputnik, dudnik and flopnik among others.