Word Study
Electro-
CIDE DICTIONARY
Electro-, [L. electrum amber. See Electric.].
A prefix or combining form signifying pertaining to electricity, produced by electricity, producing or employing electricity, etc.; as, electro-negative; electro-dynamic; electro-magnet. [1913 Webster]
OXFORD DICTIONARY
Electro-, comb. form Electr. of, relating to, or caused by electricity (electrocute; electromagnet).
Etymology
Gk elektron amber: see ELECTRIC
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