semidiurnal

adjective

semi·​di·​ur·​nal ˌse-mē-dī-ˈər-nᵊl How to pronounce semidiurnal (audio)
ˌse-ˌmī-,
-mi-
1
: relating to or accomplished in half a day
2
: occurring twice a day
3
: occurring approximately every half day
the semidiurnal tides

Word History

First Known Use

1594, in the meaning defined at sense 1

Time Traveler
The first known use of semidiurnal was in 1594

Dictionary Entries Near semidiurnal

semidine

semidiurnal

semidiurnal arc

See More Nearby Entries 

Cite this Entry

“Semidiurnal.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/semidiurnal. Accessed 25 Apr. 2024.

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