A long knife was a type of traditional weapon used by various species and beings throughout the galaxy. The long knife was, in essence, a long version of a knife, shorter than a sword, and used almost exclusively as a close-quarters melee weapon.
Chay Praysh's Drach'nam guards used long knives in his palace. The knife sported a hilt with spikes on it, but it was ineffective against lightsabers. As the guards did not have vibroblades, they carried with their long knives neuronic whips.