Aufbau

In atomic physics and quantum chemistry, the Aufbau principle, also called the Aufbau rule, states that in the ground state of an atom or ion, electrons first fill subshells of the lowest available energy, then fill subshells of higher energy. For example, the 1s subshell is filled before the 2s subshell is occupied.
(Buchan, 1995:132)

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This word scored a eight on a three part scale of allusiveness, political oomph and cultural capital