theorize

verb

the·​o·​rize ˈthē-ə-ˌrīz 

ˈthir-ˌīz

theorized; theorizing

intransitive verb

: to form a theory : speculate

transitive verb

1

: to form a theory about

2

: to propose as a theory

theorization

ˌthē-ə-rə-ˈzā-shən 

ˌthir-ə-

noun

theorizer noun

Examples of theorize in a Sentence

Many scientists have theorized about the possibility of life on other planets.

Recent Examples on the Web

With masses equivalent to millions or even billions of suns, supermassive black holes are too massive to have been born from dying stars; instead, it is theorized that they are created when smaller black holes collide and merge, and a chain of progressively larger and larger mergers. —Robert Lea, Space.com, 12 Sep. 2025

Adell returned to action on Wednesday, but Montgomery theorized that the flight to Seattle on Wednesday evening set him back. —Jeff Fletcher, Oc Register, 12 Sep. 2025

Much of the conspiracy theorizing over Balaji’s death has to do with the refusal of his parents to accept the official findings and insistence that he was murdered. —Preston Fore, Fortune, 11 Sep. 2025

The romantic melody has been widely theorized to reference now-fiancé Kelce. —Sabrina Weiss, PEOPLE, 11 Sep. 2025

Word History

First Known Use

1644, in the meaning defined at transitive sense 1

Rhymes for theorize

• advertise
• aggrandize
• agonize
• alibis
• alkalies
• alkalis
• amortize
• amplifies
• analyse
• analyze
• anywise
• authorize

Kids Definition

theorize

verb

the·​o·​rize ˈthē-ə-ˌrīz 

theorized; theorizing

: to form a theory : speculate

theorizer noun