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morning glory

American  
Or morning-glory

noun

  1. any of various plants, especially of the genera Ipomoea and Convolvulus, as I. purpurea, a twining plant having cordate leaves and funnel-shaped flowers of various colors, often opening only in the morning.

  2. a racehorse that runs faster in morning workouts than in afternoon races.

morning-glory British  

noun

  1. any of various mainly tropical convolvulaceous plants of the genus Ipomoea and related genera, with trumpet-shaped blue, pink, or white flowers, which close in late afternoon

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of morning glory

An Americanism dating back to 1805–15

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.