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energía f. (Noun) "energy"
Early 17th cent. Borrowed from Late Latin energia 'id.,' itself borrowed from Ancient Greek ἐνέργεια ‎(enérgeia) "activity." Derived from ἔργον (ergon) "work," "labor." Mycenaean we-ka-ta. From Proto-Indo-European *u̯erǵ- "to work."
Indo-European
Celtic
Gaulish, first element in uergo-bretus "chief magistrate"
Germanic
Old Norse verk, Old High German werc, Old Saxon werk, Old English weorc (English work)
Hellenic
Doric ϝέργον (wérgon)
Armenian
Armenian gorc
Indo-Iranian
Sanskrit ū́rj- "strength," Avestan varəzəm