"Decebal" is a kind of construction for "he is able to kill ten" in the Dacian language (dece-, as you can see, is a old Indo-European root for "ten" like "decem" in Latin).
The name Decebal is composed by two words: "Dece" with the meaning: "Daci"-(ancient tribe) and "Bal/balus" an Indo-European word meaning: "the power of". The original name of king Decebal was Diurpaneus.
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