stand firm vs fight back

stand firm and fight back both are verbs.

Word	Noun	Adjective	Verb	Adverb
stand firm	No	No	Yes	No
fight back	No	No	Yes	No

As verbs, fight back is a hypernym of stand firm; that is, fight back is a word with a broader meaning than stand firm:

Other hypernyms of stand firm include defend, fight, fight down, oppose.

stand firm (verb)	fight back (verb)
refuse to abandon one's opinion or belief	fight against or resist strongly
stand up or offer resistance to somebody or something	defend oneself