clear vs clearheaded

clear is a noun but clearheaded is not a noun.

Word	Noun	Adjective	Verb	Adverb
clear	Yes	Yes	Yes	Yes
clearheaded	No	Yes	No	No

clear (noun)	clearheaded (noun)
a clear or unobstructed space or expanse of land or water
the state of being free of suspicion

clear (adjective)	clearheaded (adjective)
readily apparent to the mind	not mentally confused; able to think clearly and act intelligently
allowing light to pass through
free from clouds or mist or haze
accurately stated or described
free from confusion or doubt
characterized by ease and quickness in perceiving
clear and distinct to the senses; easily perceptible
freed from any question of guilt
easily deciphered
clear of charges or deductions
free from flaw or blemish or impurity
(especially of a title) free from any encumbrance or limitation that presents a question of fact or law
affording free passage or view
free of restrictions or qualifications
characterized by freedom from troubling thoughts (especially guilt)
(of sound or color) free from anything that dulls or dims
free from contact or proximity or connection

clear (verb)	clearheaded (verb)
remove
rid of obstructions
make clear, bright, light, or translucent
free (the throat) by making a rasping sound
make a way or path by removing objects
remove the occupants of
remove (people) from a building
rid of instructions or data
make free from confusion or ambiguity; make clear
pronounce not guilty of criminal charges
grant authorization or clearance for
settle, as of a debt
pass by, over, or under without making contact
pass an inspection or receive authorization
go away or disappear
earn on some commercial or business transaction; earn as salary or wages
yield as a net profit
make as a net profit
be debited and credited to the proper bank accounts
sell to get rid of
clear from impurities, blemishes, pollution, etc.
free from payment of customs duties, as of a shipment
go unchallenged; be approved
become clear

clear (adverb)	clearheaded (adverb)
in an easily perceptible manner
entirely