Synodic day
ROTATION PERIOD OF A BODY RELATIVE TO THE PRIMARY OBJECT IT ORBITS, E.G. SOLAR DAY
Solar day; Solar days; Synodic rotation period; Synodic rotation
A synodic day (or synodic rotation period or solar day) is the period for a celestial object to rotate once in relation to the star it is orbiting, and is the basis of solar time.