theoretically

American  

[thee-uh-ret-ik-lee] / ˌθi əˈrɛt ɪk li /

adverb

1. in principle; according to reasonable assumptions or rules, as opposed to what actually happens.

   Theoretically they are free to work, but in practice they can’t because we do not recognize their credentials.

2. in a way that is purely speculative; hypothetically.

   It seems that theoretically the central bank could constrain government spending by allowing treasury checks to bounce.

3. according to, or in a way that relates to, a scientific theory.

   An alloy with a particular composition can be modeled to determine theoretically whether it has suitable mechanical and physical properties for medical applications.

4. in a way that relates to the set of principles or methods belonging to a particular subject, art, or activity.

   Taking classes in all four fields—politics, economics, history, and culture—allows students to be grounded theoretically in the humanities and social sciences.

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Other Word Forms

• antitheoretically
  adverb
• nontheoretically
  adverb
• untheoretically
  adverb

Etymology

Origin of theoretically

theoretical ( def. ) + -ly

Example Sentences

Theoretically, making a bet could give someone the perverse incentive to start a fire, or help one grow.

From Slate • Jun. 30, 2026

Theoretically, SpaceX stands to make tens of billions of dollars from the three compute deals.

From MarketWatch • Jun. 27, 2026

"And we said, hey, that's the stuff we typically use. Theoretically, this should work. Let's go figure out how."

From Science Daily • Jun. 10, 2026

Theoretically, at its top supported speed, the X Ultra S could help you run an elite four-minute mile.

From The Wall Street Journal • May 21, 2026

Theoretically, as the uranium nucleus split in two, more neutrons would break free and fly off on their own.

From "Bomb" by Steve Sheinkin