To hypothesize is defined as to have a theory or an assumption.(verb)
An example of to hypothesize is reasoning that someone sold the car because they needed the money.
See hypothesize in Webster's New World College Dictionary
See hypothesize in American Heritage Dictionary 4
verb hy·poth·e·sized, hy·poth·e·siz·ing, hy·poth·e·siz·es verb, transitive
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