From Longman Dictionary of Contemporary Englishwhite elephantˌwhite ˈelephant noun [countable] USELESSsomething that is completely useless, although it may have cost a lot of money When the theatre first opened it was widely regarded as a white elephant.
Examples from the Corpus
white elephant• Saracen ambassadors bring Charlemagne a white elephant complete with exotic trappings.• The dam has become something of a white elephant.• Cake and white elephant stalls plus a grand prize draw.• More spaces are needed at less cost not another white elephant office block.• What do you do with a huge white elephant like that?• There's this picturesque white elephant development on the Costa del Sol, apparently going for a song.From Longman Business Dictionarywhite elephantˌwhite ˈelephant noun [countable] something that is completely useless, even though it cost a lot of moneyThe hotel is unfinished and structurally unsound - a white elephant of epic proportions.Origin white elephant (1800-1900) From the supposed practice of the King of Siam, who gave to people he did not like a white elephant, which cost a very large amount of money to keep 