alpha vs important

alpha is a noun but important is not a noun.

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

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

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