in theory
idiom
1
—used to say what should happen or be true if a theory is correct
In theory, the reading skills of the students should improve.
2
—used to say that something seems to be true or possible as an idea but may not actually be true or possible
I agree with you in theory, but realistically I don't think we have the time to do that.
Examples of in theory in a Sentence
Recent Examples on the Web
Both countries are members of the Five Eyes intelligence-sharing alliance, meaning that information gathered through Silent Courier could, in theory, be shared with Washington.
—
Adam Bearne, NPR, 14 Oct. 2025
Earlier models had shown that Bennu's path included several potential gravitational keyholes that could, in theory, redirect it toward Earth sometime in the 22nd century.
—Sharmila Kuthunur, Space.com, 13 Oct. 2025
How acquiring Erik Karlsson might have been great in theory for another run at the Stanley Cup, but was not ideal in practice.
—Eric Stephens, New York Times, 11 Oct. 2025
So lowering interest rates in theory would spur investment in economic growth.
—Hugh Cameron, MSNBC Newsweek, 7 Oct. 2025
See All Example Sentences for in theory
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Adam Bearne, NPR, 14 Oct. 2025
Earlier models had shown that Bennu's path included several potential gravitational keyholes that could, in theory, redirect it toward Earth sometime in the 22nd century.
—Sharmila Kuthunur, Space.com, 13 Oct. 2025
How acquiring Erik Karlsson might have been great in theory for another run at the Stanley Cup, but was not ideal in practice.
—Eric Stephens, New York Times, 11 Oct. 2025
So lowering interest rates in theory would spur investment in economic growth.
—Hugh Cameron, MSNBC Newsweek, 7 Oct. 2025
See All Example Sentences for in theory
Cite this Entry
“In theory.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/in%20theory. Accessed 20 Oct. 2025.
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