Inauguration Day

American  

noun

1. the day on which the president of the United States is inaugurated, being January 20 of every year following a year whose number is divisible by four. Prior to the Twentieth Amendment to the Constitution (ratified February 6, 1933), it was March 4.

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Inauguration Day British  

noun

1. the day on which the inauguration of a president of the US takes place, Jan 20

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Example Sentences

Since Inauguration Day 2025, the S&P 500 has risen by more than 13%, according to Dow Jones Market Data.

From MarketWatch • Apr. 8, 2026

American investors were humming “Hail to the Chief” last January, with stocks up in the weeks before Inauguration Day.

From The Wall Street Journal • Jan. 23, 2026

Trump signed an executive order on Inauguration Day that kept the app running in the U.S.

From Barron's • Dec. 19, 2025

I was just finishing writing my book on Inauguration Day and John Roberts swore Trump in, and the president swore an oath to uphold the Constitution, to faithfully execute it.

From Slate • Dec. 1, 2025

In addition, she was too young to run; the US Constitution requires that the president be at least thirty-five years old, and she would still have been thirty-four on Inauguration Day.

From "Votes for Women!" by Winifred Conkling