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
But, if ever adopted, these reactors could, in theory, be retrofitted to Korean and Japanese submarines, further enhancing their capabilities.
—
Christopher McFadden, Interesting Engineering, 1 Dec. 2025
You’re being invited to believe in your future self, not just in theory, but through consistent rituals and courageous choices.
—Dossé-Via Trenou, Refinery29, 30 Nov. 2025
The work makes sense in theory — but struggles to anchor once the consultants leave.
—Louisa Loran, Fortune, 29 Nov. 2025
Counting on naps or swapping meetings with my husband is better in theory than practice.
—Ginny Hogan, Parents, 28 Nov. 2025
See All Example Sentences for in theory
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Christopher McFadden, Interesting Engineering, 1 Dec. 2025
You’re being invited to believe in your future self, not just in theory, but through consistent rituals and courageous choices.
—Dossé-Via Trenou, Refinery29, 30 Nov. 2025
The work makes sense in theory — but struggles to anchor once the consultants leave.
—Louisa Loran, Fortune, 29 Nov. 2025
Counting on naps or swapping meetings with my husband is better in theory than practice.
—Ginny Hogan, Parents, 28 Nov. 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 5 Dec. 2025.
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