Since ž is the last letter of the Croatian alphabet, žnj would be near the bottom of a lexicographically ordered list. Furthermore, žnj sounds inherently funny - it's pronounced [ʒɲ̩]. Vowelless words aren't that unusual in Croatian, as it allows [r] as a syllable nucleus, but žnj is the only instance of a syllabic palatal nasal I can think of. It can be used as an indeclinable adjective. For example, "izgubili su od nekog žnj kluba" means "they lost (the football match) to some žnj club", with the implication that the listener probably hasn't heard of the football club in question, and that the loss was embarrassing.