Definitions for "Sun-synchronous orbit"
A polar orbit which is synchronous with the Sun, usually at an altitude of between 600-800 km (SSO)
An orbit in which a satellite is always in the same position with respect to the rotating Earth at the same time of day. [NOAA
Orbit whose plane rotates about the polar axis at the same rate as the Earth revolves about the Sun, i.e. one complete rotation a year.