Fulmen

Iron fulmina (Latin plural: "lightning-bolts") were crossed lightning bolt insignia of some units of the Roman army.^[1] Shields of the Legio XII Fulminata showed the spread fires of trident-shaped lightning bolts (Latin: trifida fulgures).^[2] The bolts were a reference to Jupiter, most senior of the Roman deities, hurling lightning bolts.

May also refer to Marziale's most used figure of speech, where the meaning of a poem is flipped in the last few sentences. (Fulmen in clausula)

References

^ Raffaele D'Amato Roman Army Units in the Western Provinces (1): 31 BC-AD 195 2016 1472815394 "From Mainz came fragments of iron fulgures (lightning-bolts) of the 1st century AD, and from Emlichheim a bronze Capricorn. These finds raise the question of whether the fulgures were generally applied in metal or only painted. The sources ..."
^ Graham Summer, Raffaele D'Amato Arms and Armour of the Imperial Roman Soldier - 2009 1473811899- Page 120 The milites of the Legio XII Fulminata were probably identified, at least at the beginning, by the lightning bolts chiselled ... [trifida] lightning bolts

[1] Raffaele D'Amato Roman Army Units in the Western Provinces (1): 31 BC-AD 195 2016 1472815394 "From Mainz came fragments of iron fulgures (lightning-bolts) of the 1st century AD, and from Emlichheim a bronze Capricorn. These finds raise the question of whether the fulgures were generally applied in metal or only painted. The sources ..."

[2] Graham Summer, Raffaele D'Amato Arms and Armour of the Imperial Roman Soldier - 2009 1473811899- Page 120 The milites of the Legio XII Fulminata were probably identified, at least at the beginning, by the lightning bolts chiselled ... [trifida] lightning bolts

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