good day

American  

interjection

1. a conventional expression used at meeting or parting during the daytime.

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good day British  

1. a conventional expression of greeting or farewell used during the day

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good day Idioms  

1. Also,. Formal ways of saying “Hello” or “Goodbye.” For example, He began rather oddly by addressing the audience with “Good day,” or “Good afternoon, ladies,” said the sales clerk as we walked out. All these greetings represent an abbreviation of the now obsolete God give you a good day (afternoon, etc.), which dates from about 1200. Also see good night.

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Etymology

Origin of good day

Middle English word dating back to 1175–1225

Example Sentences

See Examples For:

good day

It’s looking like a good day for artificial-intelligence stocks, which often means Apple—something of an anti-AI play—gets left behind.

From Barron's ● Oct. 9, 2026

“It’s a good day for our children,” Newsom said.

From The Wall Street Journal ● Sep. 10, 2026

“It’s a good day for the state of California.”

From The Wall Street Journal ● Sep. 10, 2026

So this date might be a good day for fans to mark in their diaries for a possible announcement.

From BBC ● Sep. 6, 2026

A friend whose dad listens to old-school R&B and likes to cha-cha in the kitchen and sing about how today was a good day.

From "A Good Kind of Trouble" by Lisa Moore Ramée