White elephant
WordNet
noun
(1) Albinic Indian elephant; rare and sometimes venerated in east Asia
(2) A valuable possession whose upkeep is excessively expensive
WiktionaryText
Etymology
In Siam elephants were working animals. However, white (albino) elephants were considered sacred and therefore were not to be put to work. The owner was then left to feed the elephant but could get no work from it. It is said that the King of Siam used to make a present of a white elephant to courtiers he wanted to ruin.
Noun
- An albino elephant.
- An ornament etc that is unwanted or is a financial burden; an unprofitable investment.