When it comes to describing something as a "household word," it means that it's widely known by almost everyone. But there are several other synonyms that can be used to convey the same meaning. Some of these words include "ubiquitous," "universal," "commonplace," "familiar," "popular," "widespread," and "well-known." These words can be used interchangeably with "household word" depending on the context in which they're used. For example, if you want to describe a brand that everyone knows, you could say it's a "ubiquitous brand" or a "popular brand." Similarly, if you want to describe a phrase that's widely used, you could say it's a "commonplace phrase" or a "well-known phrase".