Merriam-Webster Collegiate Dictionary - ivory tower

 noun  Etymology: translation of French tour d'ivoire  Date: 1911  1. an impractical often escapist attitude marked by aloof lack of concern with or interest in practical matters or urgent problems  2. a secluded place that affords the means of treating practical issues with an impractical often escapist attitude; especially a place of learning  • ivory-tower adjective  • ivory-towerish adjective