theory
noun
Simple meaning
a set of ideas that explains facts and predicts new ones
Pronunciation
Say it like this:
thihreeSay the bold part a little louder.
IPA pronunciation (US)
ˈθɪɹi
This word is pronounced essentially the same in American and British English, so one transcription covers both.
IPA (International Phonetic Alphabet) is a standard way of writing speech sounds.
Definition
Everyday modern meanings first, grouped by part of speech.
noun
sciences
A coherent statement or set of ideas that explains observed facts or phenomena and correctly predicts new facts or phenomena not previously observed, or which sets out the laws and principles of something known or observed; a hypothesis confirmed by observation, experiment etc.
A description of an event or system that is considered to be accurate.
uncountable
The underlying principles or methods of a given technical skill, art etc., as opposed to its practice.
informal
A hypothesis or conjecture.
Word at a Glance
- Difficulty
- A1 · Beginner (estimated)
- Frequency
- Very Common
- Typical Use
- General English
Word Aura™
How this word commonly comes across.
Aura for this meaning
This meaning: (sciences) A coherent statement or set of ideas that explains observed facts or phenomena and correctly predicts new facts or phenomena not previously observed, or which sets out the laws and principles of something known or observed; a hypothesis confirmed by observation, experiment etc.
Used this way, theory is a specialist word that usually carries little praise or criticism of its own. This is a legal use: the wording is institutional and carries a defined meaning in law rather than a loose everyday one.
- Emotional tone
- Neutral
- Formality
- Specialist/technical
- Intensity
- Not strongly marked
- How common
- Specialized
- Connotation
- Clinical and technical
- Usage feel
- Technical and specialized
Where it naturally appears
- Law/legal
- Government/politics
- Academic writing
- Technical/specialist writing
Usage note
In general conversation this sense usually needs explaining — outside its field, people reach for a plainer word.
Word Aura describes common impressions, not a measurement. Tone changes with sentence, speaker, relationship and situation.
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Common Patterns and Combinations
How this word naturally appears with others.
Word Family
Related forms, grouped by how they connect.
Word family
Words built from the same root.
Someone who theorizes (especially in science or art).
Compound terms
Established multiword terms.
Theory that describes aqueous solutions in terms of acids (which dissociate to give hydrogen ions) and bases (which dissociate to give hydroxyl ions).
Theory that describes aqueous solutions in terms of acids (which dissociate to give hydrogen ions) and bases (which dissociate to give hydroxyl ions).
A scientific theory of the origin of species of plants and animals.
A theory of competition stated in terms of gains and losses among opposing players.
The theory that any two particles of matter attract one another with a force directly proportional to the product of their masses and inversely proportional to the square of the distance…
The theory that any two particles of matter attract one another with a force directly proportional to the product of their masses and inversely proportional to the square of the distance…
Related words
Connected by subject or meaning, not by word formation.
In theory.
Related Words
Connected to the same idea, not synonyms.
- hypothesisnoun
- empiricaladjective
- notionnoun
More about this wordSynonyms, forms, origin
Synonyms
Sense: coherent statement
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Dictionary data from Wiktionary via the Free Dictionary API. Simple meanings, combinations and word intelligence are built from verified reference data, no AI is used to load this page.