external vs externality

external and externality both are nouns.

Word	Noun	Adjective	Verb	Adverb
external	Yes	Yes	No	No
externality	Yes	No	No	No

external (noun)	externality (noun)
outward features	the quality or state of being outside or directed toward or relating to the outside or exterior

external (adjective)	externality (adjective)
happening or arising or located outside or beyond some limits or especially surface
coming from the outside
from or between other countries
purely outward or superficial