Pierre Teilhard de Chardin coined megasynthesis in French in Le phénomène humain, completed in 1940, but published posthumously in 1956. He introduced the word to denote a vision of all the divergent streams of evolution during its fourteen billion of years of development converging in a megasynthesis of everything, at evolution’s Omega Point.
In the Hegelian dialectical process, synthesis denoted a new and higher level of truth, resolving the conflict between thesis and antithesis.