The clustering approach is one of the most promising solutions for establishing virtual backbones in wireless sensor/mesh networks (WSN/WMNs). The most basic network clustering structure that has been investigated is based on dominating sets. Usually, nodes in a dominating set consume more energy than nodes outside the set. A simple mechanism to prolong the life cycle of each node in the network by balancing their energy consumption is to rotate the active dominating set through a set of disjoint dominating sets. In this paper, we propose a novel loosely coupled dominating set (LCDS) for cluster-based WSN/WMNs, which is adapted from the concept of a weakly connected dominating set (WCDS) by further relaxing its connectivity requirement. The main advantages of the proposed LCDS are as follows. First, it decreases the average utilization of the chosen cluster heads to prolong their life cycles. Second, it increases the edge coverage of the network to exploit the benefits of load balancing. Third, it provides the network with higher reliability by supporting more alternative routing paths. Performance comparisons between the LCDS and the WCDS are given in a rotation scenario with three disjoint dominating sets. Numerical results show that the proposed LCDS outperforms the WCDS in every node deployment scenario and every performance aspect.