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

“Just in the middle of 13 in a row, I felt this was a good day to kind of sit and watch a ballgame,” Roberts said before the game.

From Los Angeles Times • May 16, 2026

In other words, you might not make as much as the unhedged S&P on a good day, but you lose a lot less on its worst days.

From Barron's • May 14, 2026

On a good day, she sees half of her old business; on a bad day, a fifth.

From The Wall Street Journal • Mar. 25, 2026

Fitzpatrick echoed those sentiments, saying: "I love Cam. He's such a nice guy. He's so laid back. I knew we were going to have a good day, and it was."

From BBC • Mar. 15, 2026

With quick nods and familiar greetings, one opened the door for her, and the other two stood a little straighter, wishing her a good day as she passed.

From "The Detective's Assistant" by Kate Hannigan