(If you look at the version in the comic, though, it's got Antarctica as a separate piece under the butterfly instead of split on the wingtips, so that's something, I suppose, even if it's not the same as a continuous map...)
It's a portmanteau of DYnamic MAXimum tensION. All the things he labeled with the term were supposed to follow a unifying design principle of maximum performance for minimal energy input, based on carefully optimized interplay of internal forces. In the case of the map, this manifested in the minimizing geographic distortion.
There is actually a second Dymaxion projection which preserves contiguity of water rather than land
I love the Dymaxion map and I was also the kid in high school chemistry class who, when we covered the allotropic forms of carbon, insisted that we also had to talk about buckminsterfullerene.