The word "abroached" is an uncommon one and may not have many synonyms. However, some possible alternatives could be "approached," "initiated," "started," "opened," or "commenced." Depending on the context, one could also consider using phrases like "began to discuss," "set in motion," or "inaugurated." It is important to note that synonyms may differ slightly in meaning and connotation, so one should choose the word that best fits the specific situation. In any case, by using a synonym for "abroached," writers can add variety to their language and avoid repetition.