PCs and printers are separate parts of HP, but are closely coupled business at the retail level.

FORBES: HP: The Case For Incoherence

Through some as yet unexplained physical process, the surface and the rest of the troposphere may be less closely coupled than scientists now assume.

ECONOMIST: A heated controversy

Climate change effects on groundwater resources are, therefore, closely linked to other global change drivers, including population growth, urbanization and land-use change, coupled with other socio-economic and political trends.

UNESCO: Climate Change Effects on Groundwater Resources: A Global Synthesis of Findings and Recommendations | United Nations Educational, Scientific and Cultural Organization