Hydrochoerinae is a subfamily of the rodent family Caviidae, commonly known as the capybara family. There are several synonyms for Hydrochoerinae, including Hydrochoerus, which is the name of the genus that includes the capybara species. Other synonyms for Hydrochoerinae include Hydrochoerus hydrochaeris, which is the scientific name for the capybara. Additionally, the term Hydrochoerus is also sometimes used as a synonym for Hydrochoerinae. Overall, these synonyms are typically used in scientific contexts when discussing capybaras and their classification within the animal kingdom, but are less commonly used in everyday language.