There are several synonyms for the phrase "reduce to submission" such as conquer, overpower, subdue, defeat, control, dominate, and suppress. All of these words imply a sense of forceful and dominant action over another individual or group. Some alternate phrases for "reduce to submission" include "bring to heel," "crush the resistance," "break the will," and "impose one's will." While these phrases have similar connotations, it is important to note that any action that involves reducing another person to submission can have negative consequences and should be avoided. Instead, it is always better to seek peaceful and respectful means of persuasion and negotiation.