long-day

American

[lawng-dey, long-] / ˈlɔŋˈdeɪ, ˈlɒŋ- /

adjective

Botany.

requiring a long photoperiod in order to flower.

long-day British

adjective

(of certain plants) able to mature and flower only if exposed to long periods of daylight (more than 12 hours), each followed by a shorter period of darkness Compare short-day

"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 long-day

First recorded in 1915–20

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

To a good approximation, Saturday ended the annual long-day season.

From Washington Post • Aug. 6, 2022

If you’re gardening north of 40 degrees North latitude, be sure to choose long-day onions.

From Seattle Times • May 13, 2022

While long-day lovers fill up their time with tasks, some of us just want to go to bed, or, better yet, remain there until a reasonable morning hour.

From Washington Post • Jun. 23, 2019

Both "long-day" and "short-day" plants can be fooled�by controlled lighting�into flowering out of season.

From Time Magazine Archive

As he hastened out to trail the long-day bitter enemies, he was framing in his mind the preliminary answers for the coroner.

From Laramie Holds the Range by Spearman, Frank H. (Frank Hamilton)

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