mean is a noun but awful is not a noun.

mean and awful both are adjectives.

mean is a verb but awful is not a verb.

mean is not an adverb while awful is an adverb.

mean (noun)	awful (noun)
an average of n numbers computed by adding some function of the numbers and dividing by some function of n

mean (adjective)	awful (adjective)
approximating the statistical norm or average or expected value	offensive or even (of persons) malicious
characterized by malice	exceptionally bad or displeasing
having or showing an ignoble lack of honor or morality	causing fear or dread or terror
marked by poverty befitting a beggar	inspired by a feeling of fearful wonderment or reverence
(used of persons or behavior) characterized by or indicative of lack of generosity	extreme in degree or extent or amount or impact
(used of sums of money) so small in amount as to deserve contempt	inspiring awe or admiration or wonder
of no value or worth
very good; of the highest quality

mean (verb)	awful (verb)
mean or intend to express or convey
have as a logical consequence
denote or connote
have in mind as a purpose
have a specified degree of importance
intend to refer to
destine or designate for a certain purpose

mean (adverb)	awful (adverb)
	used as intensifiers