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theory

the·o·ry

theory

 
 
pronunciation:
thir i
features:
Word Explorer
part of speech: noun
inflections: theories
definition 1: a reasonable, widely accepted explanation for why something happens.
After studying plants and animals in South America, Charles Darwin worked out the theory of evolution by natural selection.
 
similar words:
assumption, hypothesis, idea
definition 2: the set of rules that forms the basis of an art or science.
This year in math class we will study set theory and number theory.
similar words:
laws, philosophy, principles, school
definition 3: a view or opinion that has not been proved.
The detective has a theory about what happened to the monkey.
similar words:
belief, feeling, guess, intuition, notion, view
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  learn, science, thought