User blog comment:Cottonmouth255/Weapon Name Origins in MH3U/@comment-3315689-20130530170612

Xiphias Gladius=Xiphias is the Greek word for swordfish and it originates from xíphos (sword).Gladius is the Latin word for sword

Stygian Acedia=Stygian originates from Stynx,The Greek river of hell that lead in the underworld.Acedia is from the syllable a-,which means no or opposite,and cedía,the Greek word for graving someone (sorry.I dont know the verb).It probably means that everyone that dies from this weapon,is left un-graved (lol)

Orcus Tonitrus=Orcus is the Latin/Italian god of death.Tonitrus has something to do with thunder