Four score is often used as a classic phrase, referring to 80 years. However, there are several synonyms that can be used to replace this phrase. One of the most common alternatives is "octogenarian," which is used to describe someone who is in their 80s. Another synonym for four score is "eight decades," which is a more precise way of referring to the same time frame. Additionally, "four twenties" can also be used to reference 80 years, as it pertains to there being four twenties in the number 80. Other phrases that can be used synonymously with four score include "a lifetime ago," "generations past," and "in the distant past".