"Rail against" is a powerful phrase used to describe strong opposition or criticism towards something or someone. When looking for synonyms for this phrase, there are several options available. These include: protest, denounce, condemn, criticize, oppose, oppose strongly, speak out against, and vehemently object. Each of these synonyms carries a similar weight and emphasizes the act of expressing discontent or disapproval in a forceful manner. Whether used in formal writing or everyday conversation, choosing the right synonym for "rail against" can make all the difference in conveying the intended tone and message of the speaker or writer.