A neologism is the term used to describe a word that has been made-up or invented by a speaker, which appears in a transcript of spontaneous speech dialogue. It can also be described as a word which does not appear in the dictionary of the primary spoken language, but which is also not a foreign word.

A neologism may be a slang word that has yet to find its way into mainstream conversation, or it may be the creation of a non-native speaker who has made for example a grammatical error. The so-called slip of the tongue may also be seen as neologisms.

It is marked with the asterisk (or star) [*] at the beginning of the "new" or neologism word.