serial number

American  

noun

1. a number, usually one of a series, assigned for identification.

   the serial number of an automobile engine.

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serial number British  

noun

1. any of the consecutive numbers assigned to machines, tools, books, etc

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Etymology

Origin of serial number

First recorded in 1895–1900

Example Sentences

Each bears a unique serial number and since 1950, winners have been prohibited from selling them on the open market without first offering them back to the organization for one dollar.

From Los Angeles Times • Mar. 12, 2026

“There’s no unique serial number on a load of lobster meat,” Burroughs said.

From The Wall Street Journal • Dec. 29, 2025

He said the device was missing a sleeve, which would have been painted orange with a serial number marking.

From BBC • Nov. 23, 2025

But collectors and watch scholars have noted that the timepiece in question featured a serial number that dated it to 1965.

From Los Angeles Times • Aug. 27, 2025

I took out pencil and paper and wrote down my name, rank, serial number, and A.P.O. number.

From "Nine Stories" by J. D. Salinger