economical vs economy

economical is not a noun while economy is a noun.

Word	Noun	Adjective	Verb	Adverb
economical	No	Yes	No	No
economy	Yes	No	No	No

economical (noun)	economy (noun)
	an act of economizing; reduction in cost
	frugality in the expenditure of money or resources
	the efficient use of resources
	the system of production and distribution and consumption

economical (adjective)	economy (adjective)
of or relating to an economy, the system of production and management of material wealth
using the minimum of time or resources necessary for effectiveness
avoiding waste