From Longman Dictionary of Contemporary Englishunsustainableun‧sus‧tain‧a‧ble /ˌʌnsəˈsteɪnəbəl/ AWL adjective unable to continue at the same rate or in the same way unsustainable economic growth
Examples from the Corpus
unsustainable• Past policies favouring over-valued currencies have proved unsustainable.• While the number of levels has endured, the rationale turned out to be unsustainable.• Maybe the age of leisure will turn out to be a brief and unsustainable interlude rather than a new dawn after all.• Self-determination has, as Lansing predicted all those years ago, raised hopes to an unsustainable level.• Instead, successive presidents continued to promise prosperity and to dole out unsustainable subsidies.• Nurse education and training at Horton would be likely to become unsustainable without a sufficient variety of placements for students.From Longman Business Dictionaryunsustainableun‧su‧stain‧a‧ble /ˌʌnsəˈsteɪnəbəl◂/ adjective1impossible to continue doing for any length of timeThe company’s growth strategy proved unsustainable in a slow sales environment.The banks claim that the cost of running the system has become unsustainable.2involving the use of materials that cannot be grown or produced againunsustainable products such as hardwoods → compare sustainable 