Geography
* Rao, West Sumatra, one of the districts of West Sumatra, Indonesia * Råö, a locality in Kungsbacka Municipality, Halland County, SwedenTransport
*Fictional entities
* Rao (comics), a fictional star in the DC Universe; Superman's planet Krypton revolved around it * Rao (''Greyhawk''), god of peace, reason, and serenity in ''Dungeons & Dragons: World of Greyhawk'' * ''Raō'', the Japanese name for Raoh, a character in ''Fist of the North Star''Mathematics
* Cramér–Rao bound, a statistical concept * Rao–Blackwell theorem, a theorem in statisticsScience
* ''Rao'' (insect), a genus of wasps in the subfamily Platygastrinae * Recent African origin of modern humans (RAO), a paleoanthropological theory * Recurrent airway obstruction (RAO), a respiratory disease in horses * Response amplitude operator (RAO), a function relating a response to an input given the input frequencyTitles
* Rao (title), cognate Hindi variations of the (originally Hindu) title Raja(h) * Rao Bahadur, a title of honour issued by the British in IndiaOther uses
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