The Collaborative International Dictionary of English v.0.48:

Loran \Lor"an\ (l[^o]r"[a^]n or l[=o]r"[a^]n), n. [Acronym, from
   LOng RAnge Navigation] (Naut., aviation)
   A system of electronic navigation in which a vessel or
   aircraft determines its latitude and longitude by measuring
   the time differences between low frequency radio
   transmissions from two stationary transmitters (slaves) and a
   stationary master transmitter. Contrary to the name, Loran is
   a medium range system, usually effective for no more than a
   few hundred miles from shore. The first commercial system was
   called Loran A; the latest (and final) development is Loran
   C. [acronym]
   [RDH]

Moby Thesaurus II by Grady Ward, 1.0:

42 Moby Thesaurus words for "loran":
   Gyrosin compass, RDF, VAR, astronavigation,
   automatic electronic navigation, celestial navigation, chronometer,
   coastwise navigation, compass, consolan, dead reckoning,
   direction finder, electronic navigation, fix, gyrocompass,
   gyroscopic compass, gyrostatic compass, inertial navigation system,
   line of position, magnetic compass, magnetic needle, navar,
   navigation, needle, omnidirectional range, omnirange, pilotage,
   plane sailing, point-to-point navigation, radar, radio beacon,
   radio compass, radio direction finder, radio navigation, sextant,
   shoran, sofar, sonar, tables, tacan, teleran, visual-aural range