transformer has definitions from the fields of physics,electricity
1
[ noun ] (physics,electricity) an electrical device by which alternating current of one voltage is changed to another voltage

Used in print

(Edwin L. Bigelow and Nancy H. Otis,...)

The latter now furnishes the area with electricity distributed from a modern sub-station at Manchester_Depot which was put into operation February 19 , 1930 and was improved in January 1942 by the installation of larger transformers .

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