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
The old system was designed to require little driver effort to track straight, which sounds good in theory, but had the unintended consequence of making minor adjustments feel vague.
—
Adam Ismail, The Drive, 29 Jan. 2026
Rather than leaving the door open in theory, take initiative in practical ways.
—Alexandra Emanuelli, Southern Living, 28 Jan. 2026
The basic fiber is biodegradable, ISO-certified for protein fibers, and, in theory, compostable.
—Srishti Gupta, Interesting Engineering, 28 Jan. 2026
Immigration is where those limits are now being tested — not in theory, but in practice.
—Jody Agius Vallejo, Oc Register, 28 Jan. 2026
See All Example Sentences for in theory
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Adam Ismail, The Drive, 29 Jan. 2026
Rather than leaving the door open in theory, take initiative in practical ways.
—Alexandra Emanuelli, Southern Living, 28 Jan. 2026
The basic fiber is biodegradable, ISO-certified for protein fibers, and, in theory, compostable.
—Srishti Gupta, Interesting Engineering, 28 Jan. 2026
Immigration is where those limits are now being tested — not in theory, but in practice.
—Jody Agius Vallejo, Oc Register, 28 Jan. 2026
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 31 Jan. 2026.
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