What is an example of neologism?

Neologism refers to the creation of a new word or expression that often lacks a specific meaning and can be nonsensical or invented. An example would be a term that is not recognized in the standard language but is created by an individual, often in a moment of linguistic creativity or whimsy.

In this context, the correct choice highlights that neologisms can be completely new formations that don't necessarily conform to existing language rules or have established meanings, making them nonsensical in nature. This is frequently seen in language use among children or individuals with certain neurological conditions, where they create words that can be imaginative yet unrecognizable to others.

The other options reflect different linguistic phenomena. Random substitution of meanings pertains more to semantic errors, while a meaningful and well-formed sentence does not fit the definition of a neologism. A literal substitution in context indicates an error or miscommunication rather than the inventive nature of a neologism.