Sparring, basically has the same meaning in almost all martial arts, martial sports, and combat sports such as boxing and Muay Thai. Wing Tsun is different however. In fact, it might not meet the definition in Wing Tsun.
In the above martial arts and sports, two combatants face off with each other. They generally walk around each other waiting for a good moment to attack. Usually a fighter is looking for an opening or a weak moment on the part of their sparring partner to attack.