A rank in the classification of organisms, also known as kingdom(noun)
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Use "regnum" in a sentence
"Amen dico vobis, nisi conversi fueritis, & efficiamini sicut parvuli, non intrabitis in regnum coelorum."
"Ninth Ordo calls the papal cap regnum, but in the description that the Ordo gives of this cap we hear nothing at all of a crown, but merely that the regnum was a helmet-like cap made of white material."
"It is called regnum paratum, a kingdom prepared, which implies something that is rare and excellent."