formidability vs toughness

formidability and toughness both are nouns.

Word	Noun	Adjective	Verb	Adverb
formidability	Yes	No	No	No
toughness	Yes	No	No	No

As nouns, formidability and toughness are synonyms defined as:

formidability (noun)	toughness (noun)
impressive difficulty	the property of being big and strong
	enduring strength and energy
	impressive difficulty
	the elasticity and hardness of a metal object; its ability to absorb considerable energy before cracking