Another property of language is that its symbols are arbitrary. Any concept or grammatical rule can be mapped onto a symbol. In other words, most languages make use of sound, but the combinations of sounds used do not have any necessary and inherent meaning – they are merely an agreed-upon convention to represent a certain thing by users of that language. For instance, the sound combination nada carries the meaning of "nothing" in the Spanish language and also the meaning "thread" in the Hindi language. There is nothing about the word nada itself that forces Hindi speakers to convey the idea of "thread", or the idea of "nothing" for Spanish speakers. Other sets of sounds (for example, the English words nothing and thread) could equally be used to represent the same concepts, but all Spanish and Hindi speakers have acquired or learned to correlate their own meanings for this particular sound pattern. Indeed, for speakers of Slovenian and other South Slavic languages, the sound combination carries the meaning of "hope", while in Indonesian, it means "tone".
This arbitrariness even applies to words with an onomatopoetic dimension (i.e. words that to some extent simulate the sound of the token referred to). For example, several animal names (e.g. cuckoo, whip-poor-will, katydid) are derived from sounds the respective animal makes, but these forms did not have to be chosen for these meanings. Non-onomatopoetic words can stand just as easily for the same meaning. For instance, the katydid is called a "bush cricket" in British English, a term that bears no relation to the sound the animal makes. In time, onomatopoetic words can also change in form, losing their mimetic status. Onomatopoetic words may have an inherent relation to their referent, but this meaning is not inherent, thus they do not violate arbitrariness.