NST meaning in Airport Code ?

Nakhon Si Thammarat Municipality (Thai: เทศบาลนครนครศรีธรรมราช, pronounced [ná(ʔ).kʰɔ̄ːn sǐː tʰām.mā.râːt]; from Pali Nagara Sri Dhammaraja) is a municipality (thesaban nakhon) in Southern Thailand, capital of the City of Nakhon Si Thammarat and the Nakhon Si Thammarat District. It is about 610 km (380 mi) south of Bangkok, on the east coast of the Malay Peninsula. The city was the administrative center of southern Thailand during most of its history. Originally a coastal city, silting moved the coastline away from the city. The city has a much larger north to south extension than west to east, which dates back to its original location on a flood-save dune. The modern city centre on the train station is north of Old Town. As of 2019, the city had a population of 102,152.