When faced with adversity, there are various ways to respond, and "fighting back" is one of them. However, there are several synonyms for "fight back" that convey slightly different meanings and nuances. For instance, "resist" emphasizes a more passive stance, while "counter" suggests a more strategic approach. "Oppose" implies more overt objection and "defend" brings up the idea of protecting oneself or others. "Rebel" can imply a more radical approach and "stand up to" highlights the notion of asserting oneself. Whichever synonym one chooses, the common thread is the need to take action in response to a perceived threat.