Restricted to theory; not practical: theoretical physics. (adjective)
Given to theorizing; speculative. (adjective)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "theoretical" in a sentence
"Despite being conveyed as purely theoretical, a recent article in the national Canadian newspaper, the Financial Post, referred to the amero, not as a theoretical idea or conspiracy theory, but as a potential reality."
"Aristotle is well aware of the limitations of what he calls theoretical wisdom."
"I don't teach abstract political science with all the, what I call theoretical, conceptual baloney."