semi·di·ur·nal adjective \-dī-ˈər-nəl\
: relating to or accomplished in half a day
: occurring twice a day
: occurring approximately every half day <the semidiurnal tides>
First Known Use of SEMIDIURNAL
Learn More About SEMIDIURNAL
Seen & Heard
What made you want to look up semidiurnal? Please tell us where you read or heard it (including the quote, if possible).