When someone says they "betted the farm," they are expressing that they put everything they had at risk for a certain outcome. However, there are various synonyms for this idiom that can be used to convey a similar meaning. For example, someone could say they "risked it all," "went all in," "put their neck on the line," or "put their fate in someone else's hands." Other synonyms include "took a leap of faith," "went for broke," "put their eggs in one basket," and "took a big gamble." All of these phrases express a willingness to take a big risk, with high stakes involved.