withstand vs defy

withstand and defy both are verbs.

Word	Noun	Adjective	Verb	Adverb
withstand	No	No	Yes	No
defy	No	No	Yes	No

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

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

As verbs, withstand and defy are synonyms defined as:

Other synonyms of withstand include hold, hold up.

withstand (verb)	defy (verb)
stand up or offer resistance to somebody or something	challenge
resist or confront with resistance	resist or confront with resistance
	elude, especially in a baffling way