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

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

It’s never a good day to be fired, but Noem’s departure comes at a particularly unfortunate moment for her.

From Slate • Mar. 5, 2026

On a good day, he takes home between 900 and 1,000 rupees, after deducting money spent on fuel and food.

From BBC • Jan. 30, 2026

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

From Los Angeles Times • Dec. 22, 2025

“Would you be interested in coming to see him? If it’s a good day, he can be quite talkative. It’s really his short-term memory that is lacking, but he may remember your mom.”

From "The Line Tender" by Kate Allen