Noun | 1. | NT - an organization concerned to preserve historic monuments and buildings and places of historical interest or natural beauty; founded in 1895 and supported by endowment and private subscription NGO, nongovernmental organization - an organization that is not part of the local or state or federal government Britain, Great Britain, U.K., UK, United Kingdom, United Kingdom of Great Britain and Northern Ireland - a monarchy in northwestern Europe occupying most of the British Isles; divided into England and Scotland and Wales and Northern Ireland; `Great Britain' is often used loosely to refer to the United Kingdom |