hotheaded vs madcap

hotheaded is not a noun while madcap is a noun.

Word	Noun	Adjective	Verb	Adverb
hotheaded	No	Yes	No	No
madcap	Yes	Yes	No	No

As adjectives, hotheaded and madcap are synonyms defined as:

hotheaded and madcap: characterized by undue haste and lack of thought or deliberation

Other synonyms of hotheaded include brainish, impetuous, impulsive, tearaway.

hotheaded (noun)	madcap (noun)
	a reckless impetuous irresponsible person

hotheaded (adjective)	madcap (adjective)
quickly aroused to anger	characterized by undue haste and lack of thought or deliberation
characterized by undue haste and lack of thought or deliberation