1. a cord that is pulled to open the gasbag of a balloon wide enough to release gas and so causes the balloon to descend;
2. a cord that is pulled to open a parachute from its pack during a descent;
WordNet (r) 3.0 (2006):
ripcord
n 1: a cord that is pulled to open the gasbag of a balloon wide
enough to release gas and so causes the balloon to descend
2: a cord that is pulled to open a parachute from its pack
during a descent