stand firm vs defy

stand firm and defy both are verbs.

Word	Noun	Adjective	Verb	Adverb
stand firm	No	No	Yes	No
defy	No	No	Yes	No

As verbs, defy is a hyponym of stand firm; that is, defy is a word with a more specific, narrower meaning than stand firm:

Other hyponyms of stand firm include stand out, stand up, outbrave, hold off, remain firm, stand, hold, hold up, withstand.

stand firm (verb)	defy (verb)
refuse to abandon one's opinion or belief	challenge
stand up or offer resistance to somebody or something	resist or confront with resistance
	elude, especially in a baffling way