(名詞) 走繩索運動。亦寫成 slack lining, slack-lining。
—slackline：(名詞) 走繩索運動用的尼龍繩，(動詞) 走繩索。
不過，這與一般所知的 tightrope walking (走拉緊的繩索) 不同；slacklining 係使用尼龍繩 (nylon rope)，因此當走繩人 (walker) 走在上面時，它就像一條大橡皮筋 (rubber band) 或跳繩 (jump rope) 會上下振動、左右搖晃。slacklining 又稱為 loose rope walking，而此尼龍繩又稱為 slack rope。slacklining 是一種集運動、心智遊戲和精神探求於一身的冒險刺激活動，在美國有日漸風行之勢。它都在距離地面約 1,000~2,000 英尺的高空進行，尼龍繩被繫在峽谷兩邊的懸崖峭壁上，走繩人身上利用一種安全裝置與繩索綁在一起；所以即使掉下去亦不會有危險。從事 slacklining 的人稱為 slackliner, slack lining walker 或 slacker。
The distinction separates slacklining from seemingly similar ventures, such as tightrope walking, in which the rope is stretched tightly and remains static. A slackline moves, however, and when a beginner follows the impulse to concentrate on keeping her feet still, it moves even more, swinging from side to side as the feet clench it with increasing intensity.
—Diana Saverin, "Slackliners find balance one step at a time," Pittsburgh Post-Gazette, December 11, 2011
If you saw the Super Bowl halftime show, you probably wondered, "Who's that guy in a toga bouncing crazily on a rope next to Madonna? And how's he doing it?" The guy was Andy Lewis, a slacklining champion from California, and he did it after many, many years of practice. Slacklining is different from tightrope walking. Instead of a taught [sic] line, it's performed on inch-thick nylon webbing that stretches and bounces.
—Marc Silver, "After the Super Bowl, Everyone's Curious About Slacklining," National Geographic News Watch, February 8, 2012