Morning glory is a type of flowering vine known for its trumpet-shaped blooms that open in the early morning and typically close by afternoon. The flowers come in vibrant colors like purple, blue, pink, and white, and they unfurl as the sun rises, which is how they got their cheerful name.

These plants climb by twining their stems around fences, trellises, or anything vertical they can grasp. Gardeners love them because they grow quickly and produce dozens of flowers throughout the summer, creating walls of color. But morning glories can also be invasive: once they start growing, they're hard to stop, and they can take over gardens or wild areas, crowding out other plants.

The term can also describe someone who performs best early in the day. If your friend is a morning glory, they're alert and energetic at breakfast but tired by evening. In sports, a morning glory might be an athlete or team that starts strong but fades as the season progresses. The phrase captures that same pattern as the flower: brilliant at the beginning, but not lasting until the end.