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 a good day if I can have a conversation with someone who doesn’t want to vaccinate, even if I don’t convince them.

From Los Angeles Times ● Jul. 28, 2026

"On a good day, there would be hundreds of people here from the morning right through until midnight, swimming and enjoying the lake, but now the place is empty," he said.

From BBC ● Jul. 26, 2026

Tuesday wasn’t a good day for International Business Machines.

From The Wall Street Journal ● Jul. 15, 2026

“The student-loan system is confusing on a good day, and we’re moving into a period where there’s likely to be heightened confusion,” she said.

From MarketWatch ● Jul. 1, 2026

Dad tells me he had a good, day.

From "Shine!" by J.J. and Chris Grabenstein