noun
diurnal motion
Astronomy term for the apparent daily motion of celestial bodies across the sky due to Earth's rotation.
星の日周運動は、地球の自転によって起こる。
The diurnal motion of stars is caused by the Earth's rotation.
Compound of 日周 (にっしゅう, 'daily cycle') and 運動 (うんどう, 'motion').