Superfluities is a term that refers to excessive or unnecessary things, and there are plenty of related synonyms that can be used interchangeably. One such synonym is extravagance, which suggests an indulgent or wasteful use of resources. Similarly, the word surplus can refer to what is left over after needs are met, or to an excess of anything. Another useful synonym is excess, which refers to an overabundance or more than is necessary. Additionally, words like redundancy, extra, and luxury can all be used to describe a surplus of goods or services that are not essential. Whatever the context, there are plenty of options for describing something that is more than is needed.