hraðeind

== Icelandic == === Etymology === From hrað- (“tachy-”) +‎ eind (“particle”), compare hraði (“speed”) and hraður (“fast”). === Pronunciation === IPA(key): [ˈr̥aːðeint] === Noun === hraðeind f (genitive singular hraðeindar, nominative plural hraðeindir) tachyon ==== Declension ==== ==== See also ==== fiseind ljósfrár, yfir ljóshraða (“superluminal”)