This page contains information regarding Star Trek: Lower Decks, and thus may contain spoilers.
The lirpa was a traditional Vulcan melee weapon, consisting of a metal staff with a fan-shaped blade on one end and a club on the other. The haft below the shaped blade had some Vulcan lettering on it.
In 2154, Vulcan commandos sent by the Vulcan High Command after Jonathan Archer and T'Pol wielded lirpas, since energy weapons were useless in Vulcan's Forge. Archer disarmed one of them and was very familiar with the use of this weapon due to having mind melded with Syrran. (ENT: "Kir'Shara")
A lirpa was part of the late Kerner Hauze's collection, displayed on a wall alongside a kar'takin, ushaan-tor, bat'leth, and mek'leth. In 2381, Ensign Beckett Mariner used it to block weapons fire from flying orbs. (LD: "Kayshon, His Eyes Open") In the same year, Malvis had a lirpa in his shop on Starbase 25. (LD: "An Embarrassment Of Dooplers")
Lirpas didn't feature in the original story outline of "Amok Time". Instead, the traditional mating challenge included different weapons in a total of three "rounds". The first was to be a weapon newly created for the episode, described in the outline as "a weapon like a mace or a 'knob-kerry' – a heavy ball, with sharp spikes, with a short chain and handle." Knives were used in the second round, and the third round was fought barehanded.