The phrase "two-year" refers to a period of time lasting for two years. Some synonyms for "two-year" include "biennial," "semi-biennial," and "biennium." "Biennial" is often used to describe events or activities that happen every two years, while "semi-biennial" is used to refer to events that occur twice a year. "Biennium" is a term that is commonly used in the legislative field to describe a two-year period between general election cycles. Other synonyms for "two-year" include "24 months," "730 days," and "104 weeks." These terms can be used interchangeably depending on the context in which they are used.