matrix organization

An organizational structure in which the project manager shares responsibility with functional managers for assessing priorities and assigning tasks to resources that may or may not be within their own workgroup.'

SOURCE; microsoft project glossary-projectlearning.net

1. Any organizational structure in which the project manager shares responsibility with the functional managers for assigning priorities and for directing the work of individuals assigned to the project.2. A two dimensional organizational structure in which the horizontal and vertical intersections represent different staffing positions with responsibility divided between the horizontal and vertical authorities.

SOURCE: apm.com