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

“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

On a good day it takes me 10 or 15 seconds to say my own name.

From The Wall Street Journal ● Jun. 22, 2026

Just keep in mind that the tired brain is not you on a good day.

From BBC ● Jun. 13, 2026

Lately, whenever stocks had a good day, Treasuries did too.

From Barron's ● Jun. 11, 2026

On a good day, Chicken liked to wander.

From "Caterpillar Summer" by Gillian McDunn