important vs alpha

important is not a noun while alpha is a noun.

Word	Noun	Adjective	Verb	Adverb
important	No	Yes	No	No
alpha	Yes	Yes	No	No

important (noun)	alpha (noun)
	the 1st letter of the Greek alphabet
	the beginning of a series or sequence

important (adjective)	alpha (adjective)
of great significance or value	early testing stage of a software or hardware product
of extreme importance; vital to the resolution of a crisis	first in order of importance
important in effect or meaning
having or suggesting a consciousness of high position
having authority or ascendancy or influence