long-day

adjective

ˈlȯŋ-ˈdā How to pronounce long-day (audio)
: responding to or relating to a long photoperiod
—used especially of a plant compare day-neutral, short-day

Word History

First Known Use

1920, in the meaning defined above

Time Traveler
The first known use of long-day was in 1920

Rhymes for long-day

See All Rhymes for long-day

Browse Nearby Words

long dance
long-day
long-distance
See all Nearby Words

Cite this Entry

“Long-day.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/long-day. Accessed 6 Jul. 2025.

Copy Citation

Share

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Popular in Grammar & Usage

See More

More Words You Always Have to Look Up

Using Bullet Points ( • )

Should that word have a hyphen?

Words You Always Have to Look Up

Democracy or Republic: What's the difference?
See More

Popular in Wordplay

See More

How 'Namaste' Entered The English Language

12 Lovely and Unusual Words for the Natural World

10 Hella Good U.S. Regionalisms

Better Ways to Say 'This Sucks'

8 Words with Fascinating Histories
See More

Popular

See More

More Words You Always Have to Look Up

How 'Namaste' Entered The English Language

12 Lovely and Unusual Words for the Natural World
See More

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
Missing Letter A daily crossword with a twist
name tags
Words Named After People Quiz Find out who’s behind "leotard," "morphine," an...
See All