NX
NX was a two-letter prefix first used by the United Earth Starfleet for their  starships in the mid-22nd century. () After the founding of the  in 2161, this prefix was used for experimental and prototype starship designs. () In the mirror universe, this prefix was used by the Terran Empire for their NX-class starships. () Two centuries later, this prefix was used by the Terran Resistance Forces for their  starship. () Ships that used the NCC and the NX prefix were listed in the Starfleet Registry. ()

NX registries

Alternate registries

Mirror universe NX registries

Appendices

Apocrypha 
Other NX ships listed in literature include:
  (Star Trek: Titan)
  ()

External link 
 

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Prefixes