rashness vs foolhardiness

rashness and foolhardiness both are nouns.

Word	Noun	Adjective	Verb	Adverb
rashness	Yes	No	No	No
foolhardiness	Yes	No	No	No

As nouns, rashness and foolhardiness are synonyms defined as:

rashness and foolhardiness: the trait of giving little thought to danger

Other synonyms of rashness include recklessness.

rashness (noun)	foolhardiness (noun)
the trait of giving little thought to danger	the trait of giving little thought to danger
the trait of acting rashly and without prudence