Some forms of one or more segmental morphemes, like English ‘act’, ‘John’, ‘hat’, ‘actor’, ‘actors’, ‘John’s’, ‘John’s hat’, ‘John’s hat is on the table’, have the property that on occasion they may occur as whole utterances, requiring only the addition of a suitable intonation. [...]. This property is ‘freedom’; forms that have it are ‘free’.
- Hockett (1958), a pag.168