Mostly bound — almost always seen in compounds: 绵延 (stretch on and on), 绵密 (meticulous), 绵软 (soft and mild), 绵羊 (sheep), 海绵 (sponge), 棉绵 (cotton wadding). The 纟 (silk) radical hints at the original meaning of 'silk floss'.
memory
Picture pulled silk floss: 'soft', 'continuous', and 'weak/yielding' all flow from that one image.
