Final answer:
A formal, often temporary, partnership involving two or more groups working together to achieve specific goals according to a common plan is called a coalition.
Step-by-step explanation:
A formal, often temporary, partnership involving two or more groups working together to achieve specific goals according to a common plan is termed a coalition. A coalition is formed when organizations or groups come together for a common purpose, pooling their resources, expertise, and efforts to achieve shared goals. For example, environmental organizations, community groups, and government agencies may form a coalition to address a specific environmental issue such as reducing pollution in a river. By collaborating and leveraging their collective strengths, these organizations can work together more effectively towards their shared goals.