Synergy
Synergy occurs when the sum (or result) of cooperating parties is greater than the sum of everyone's contribution. The term is derived from the Greek synergia, which means working together.
The term can refer both to cooperating parties that remain independent and to companies that join forces through a merger, acquisition or joint venture. In addition to cooperation between companies or business units, synergy can also refer to different activities or processes within the organization.
Activities involved can be equal to each other or supportive. In all cases, for synergy to occur, the parts reinforce each other such that the whole becomes greater than the sum of its parts.
Besides synergy, there is also the term synergism. Whereas synergy refers mainly to the positive effect of cooperation, synergism refers to all the consequences of cooperation, which can also be negative. The adjective of synergy is synergistic.