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

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Browse Nearby Words

long dance
long-day
long-distance
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Cite this Entry

“Long-day.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/long-day. Accessed 8 Jul. 2025.

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