peruse |pəˈroōz|verb [ trans. ] formalread thoroughly or carefully : the pursed lips of an auditor perusing an unsatisfactory set of accounts.• examine carefully or at length : Laura perused a Caravaggio.DERIVATIVESperuser nounORIGIN late 15th cent. (in the sense ‘use up, wear out’ ): perhaps fromper- [thoroughly] + use , but compare with Anglo-Norman Frenchperuser ‘examine.’USAGE The verb peruse means ‘read thoroughly and carefully.’ It is sometimes mistakenly taken to mean ‘read through quickly, glance over,’ as in : later documents will be perused rather than analyzed thoroughly, a sentence that technically makes no sense.