theorem

noun

the·​o·​rem ˈthē-ə-rəm 

ˈthir-əm

1

: a formula, proposition, or statement in mathematics or logic deduced or to be deduced from other formulas or propositions

2

: an idea accepted or proposed as a demonstrable truth often as a part of a general theory : proposition

the theorem that the best defense is offense

3

: stencil

4

: a painting produced especially on velvet by the use of stencils for each color

theorematic

ˌthē-ə-rə-ˈma-tik 

ˌthir-ə-

adjective

Examples of theorem in a Sentence

Recent Examples on the Web

There are theorems that have been proven and loopholes discovered to those theorems, some of which have been closed and some of which remain open, and this remains an active and exciting area of research. —Ethan Siegel, Big Think, 23 Sep. 2025

This is a direct consequence of no-go theorems like no-cloning, no-deleting, no-hiding and uncertainty—any attempt to eavesdrop alters the quantum signal, alerting the sender and receiver. —Pravir Malik, Forbes.com, 19 Sep. 2025

Analysis of the gravitational signal from a black hole merger detected in January provides the best observational evidence to date in support of Hawking's theorem, according to a new paper published in the journal Physical Review Letters. —Jennifer Ouellette, ArsTechnica, 11 Sep. 2025

Thanks to data with four times better resolution, scientists are now much more confident that Hawking’s theorem is correct. —Mrigakshi Dixit, Interesting Engineering, 10 Sep. 2025

Word History

Etymology

Late Latin theorema, from Greek theōrēma, from theōrein to look at, from theōros spectator, from thea act of seeing — more at theater entry 1

First Known Use

1551, in the meaning defined at sense 1

Phrases Containing theorem

• Bayes's theorem
• Bayes theorem
• binomial theorem
• central limit theorem
• DeMoivre's theorem
• Fermat's last theorem
• Fourier's theorem
• Godel's theorem
• Jordan curve theorem
• mean value theorem
• Pythagorean theorem
• remainder theorem
• Rolle's theorem

Rhymes for theorem

• variorum
• antiserum
• serum
• thiram

Kids Definition

theorem

noun

the·​o·​rem ˈthē-ə-rəm 

ˈthi(-ə)r-əm

1

: a formula, proposition, or statement in mathematics or logic that has been or is to be proved from other formulas or propositions

2

: an idea accepted or proposed as a demonstrable truth