A somewhat formal greeting generally used between sunrise and sunset.(interjection)
A dismissal; sometimes used to express annoyance.(interjection)
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Use "good day" in a sentence
"I had a feeling that a good day for Ms. Torrance would probably be a pretty bad day for me."
"“And good day in return, Mistress Clark, for so I believe you are called,” said the visitor, sweeping inside."
"“Low-Cost Tractor Forks!” when Sherri suddenly calls out from the stove, “Oh West, hon, the weatherman said the pollen count is low right now, so this would be a good day for you to take care of those weeds by the mailbox.”"