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

Once these cables meet land, they’ll connect to a new substation near Humboldt Harbor.

From Los Angeles Times • Apr. 9, 2026

On a recent day, a group of emergency energy engineers gathered at a transformer substation to carry out repairs after residents turned on all their equipment at once when power was restored, overloading the system.

From The Wall Street Journal • Feb. 15, 2026

The state-owned Union Electrica de Cuba said on X that a problem at a substation in Holguin Wednesday night caused an electrical system disconnect that impacted the four provinces.

From Barron's • Feb. 5, 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

They run, as carefully and as quickly as they can, until they reach the wide platform of a substation.

From "The Kill Order (Maze Runner, Book Four; Origin)" by James Dashner