Synonyms, or closely associated words and phrases, are incredibly important tools in building fictional worlds. They can be used to help set a tone, can be used to avoid unwanted repetition, and can aid in creating a sense of richness and immensity to a world. Placenames are especially important areas where synonyms can be handy. Designers may frown at the idea of town, after town, after town in their world, and scattering the landscape with a village, hamlet, and shire may alleviate this. Additionally, while it may not quite sit right that the main villain has their seat of power in a castle, it may be a better fit for them to reign from a citadel or fortress. Worldbuilders should always consider synonyms for the elements they include in their fictional worlds.

Other Atlas lists both common real world synonyms and example mythonyms next to each element at the top of their page.