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

Robo-taxis look like one reason Tesla stock is having a good day.

From Barron's

“Today is a good day to prepare as we know more rain is coming.”

From Los Angeles Times

On the good days we try to hold on to hope.

From BBC

"On a good day, I might be good. I think of my writing as contemporary accessible fiction and it really isn't for me to add the qualifying adjectives."

From BBC

Brendan Cummings, conservation director for Center for Biological Diversity, hailed the moment as “a good day, not just for mountain lions, but for Californians.”

From Los Angeles Times