The word "hadst at" can be a confusing term for many, as it is not commonly used in modern English. However, there are several synonyms for this archaic verb, which means "to have or hold against." Some of these synonyms include accuse, blame, impute, reproach, censure, indict, and charge. These words are commonly used in legal proceedings or when someone is being held responsible for something. It is important to note that these synonyms may have different connotations, nuances, and levels of severity. Therefore, it is essential to choose the appropriate word according to the context and tone of the sentence.