QSO may refer to:
*Quasi-stellar object or
quasar
A quasar ( ) is an extremely Luminosity, luminous active galactic nucleus (AGN). It is sometimes known as a quasi-stellar object, abbreviated QSO. The emission from an AGN is powered by accretion onto a supermassive black hole with a mass rangi ...
*
Queen's Service Order, New Zealand honour
*
Queensland Symphony Orchestra
*
The Quantic Soul Orchestra
*
QSO, a Q code used in commercial and amateur radio communication
*The IATA airport code for
Sousse
Sousse, Sūsah , or Soussa (, ), is a city in Tunisia, capital of the Sousse Governorate. Located south of the capital Tunis, the city has 271,428 inhabitants (2014). Sousse is in the central-east of the country, on the Gulf of Hammamet, which ...
, Tunisia
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