withstand vs fight back

withstand and fight back both are verbs.

Word	Noun	Adjective	Verb	Adverb
withstand	No	No	Yes	No
fight back	No	No	Yes	No

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

Other hypernyms of withstand include defend, fight, fight down, oppose.

withstand (verb)	fight back (verb)
stand up or offer resistance to somebody or something	fight against or resist strongly
resist or confront with resistance	defend oneself