: 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

Dictionary Entries Near long-day

Cite this Entry

“Long-day.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/long-day. Accessed 8 May. 2024.

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