Definitions: (1) working together in harmony; cooperative; (2) characterizes separate agents, persons, or qualities that [when acting in unison] have a greater total effect than the sum of their individual values; superadditive; (3) describes a balanced or symmetrical collaboration; teamwork

Synonyms: A synectic exercise is the bringing together of a select group of diverse personalities and areas of expertise for creative thinking about a specific problem with the free use of metaphor and analogy; brainstorming is the spontaneous contribution of ideas, no matter how obscure, in the hope of solving a specific problem or to generate a general stimulation of creative thinking.

Quote: Synergy is what happens when one plus one equals ten or a hundred or even a thousand! It’s the profound result when two or more respectful human beings determine to go beyond their preconceived ideas to meet a great challenge. — Steven Covey (1932-2012) American inspirational speaker

Observation: Any chemist can tell you about the synergistic/superadditive (definition #2 above) results which occur all around us. The most abundant example is water. From hydrogen, which burns freely, and oxygen, which supports fire, we get a substance essential to extinguish many combustible substances – not to mention its life-giving characteristics.
     Another example is salt. From sodium, an extremely reactive metal, and chlorine, a poisonous gas, comes one of the most necessary substances for human health.

Symbols: 1) Sagittarius (Zodiac); 2) the hurricane {Cosmic Synergy} (American Indian)