adjectiveaidiacht1impossible to maintainneamh-inbhuanaitheadj3it was financially unsustainablení raibh sé inbhuanaithe ó thaobh an airgid de2ecologyéiceolaíochtenvironmentally damagingneamh-inbhuanaitheadj3air travel is environmentally unsustainableníl an t-aerthaisteal inbhuanaithe ó thaobh na timpeallachta de3impossible to support, defendthis approach is demonstrably unsustainableis léir nach bhfuil aon dealramh leis an gcur chuige seoan unsustainable ideasmaoineamh gan dealramh