The word "sasses back" means to talk back in a disrespectful or impolite manner. There are many synonyms for this phrase, including "rebukes," "defies," "challenges," "contradicts," "opposes," "refutes," "argues," "disobeys," "opposes," and "defiantly responds." These words are useful when describing someone who is being rude or insolent while speaking to authority figures or elders. It is important to choose the appropriate synonym for the context or situation in which it is used, as each word may carry a slightly different connotation or degree of disrespect. In any case, it is generally not considered acceptable to "sass back" in most social situations.