theories
- 1Plural of theory.
Competing theories about the origin of the universe still divide physicists.
Her lectures wove together economic theories from several different schools of thought.
Note
A plural that only some meanings of theory can take. Rival explanations count easily, as in competing theories or two theories of the crime. So do the logician's formal theories, each a set of axioms with everything derivable from them. The sense of principles as opposed to practice does not pluralize: a student learns music theory, not music theories. The spelling follows the consonant-plus-y rule of category and quantity.
theories is a form of theory
theory, noun: An idea or explanation put forward for why something happens or how something works, especially one that has not been proved. Full entry
- Forms
- theorytheories plural
- Spelling
- theory → theories: change y to i, add -es
Use it in a sentence
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