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

“I grew up in a world as a trader where if I was wrong 49% of the time, that was a pretty good day, so I’m not afraid of putting out a forecast,” she said.

From The Wall Street Journal ● Oct. 11, 2026

The Dodgers could trade a few bad days from Ohtani for that one really good day.

From Los Angeles Times ● Oct. 3, 2026

"I'm crystal ball gazing and can do it reasonably well on a good day, but nowhere near with the clarity of the nanopore, which gives a comprehensive molecular classification," he said.

From BBC ● Sep. 24, 2026

"Today is a good day for democracy, the rule of law, and the American people looking to exercise their Constitutional right to vote," the governor said in a statement.

From Barron's ● Sep. 15, 2026

All in all, it had been a pretty good day.

From "The Smartest Kid in the Universe" by Chris Grabenstein