substation

American  

[suhb-stey-shuhn] / ˈsʌbˌsteɪ ʃən /

noun

1. a branch of a main post office.

2. an auxiliary power station where electrical current is converted, as from AC to DC, voltage is stepped up or down, etc.

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substation British  

/ ˈsʌbˌsteɪʃən /

noun

1. a subsidiary station

2. an installation at which electricity is received from one or more power stations for conversion from alternating to direct current, reducing the voltage, or switching before distribution by a low-tension network

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Etymology

Origin of substation

First recorded in 1885–90; sub- + station

Example Sentences

Thanks to its vertically integrated structure, Forgent can deliver substation transformers in roughly 30 weeks, compared with industry averages of 80 weeks or more, J.P.

From Barron's • Mar. 2, 2026

West Virginia is now on the frontline of a national shift that most people won’t notice until it shows up in their own bills, water tables or the substation down the road.

From Salon • Dec. 28, 2025

“The damage from the fire in our substation was significant and extensive and the repairs and safe restoration will be complex,” PG&E posted Sunday morning on X. “We have mobilized additional engineers and electricians.”

From Los Angeles Times • Dec. 21, 2025

It would include infrastructure for connection to the National Grid at Cottam substation in Nottinghamshire.

From BBC • Oct. 14, 2025

They found themselves in a tiny substation, empty, airless, ruined.

From "I, Robot" by Isaac Asimov