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 utility also replaced 38% fewer substation transformers than it said it would.

From Los Angeles Times • Dec. 17, 2025

The utility said that xAI’s construction of a substation wouldn’t impact residential rates, which are set by the utility’s board of commissioners and approved by the city council.

From The Wall Street Journal • Oct. 6, 2025

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

From "I, Robot" by Isaac Asimov