= Solution
An <electron configuration> specifies the occupied one-electron subshells and their populations, such as $1s^22s^22p^2$, without fixing how all orbital and <spin> <angular momenta> are coupled.
An <atomic term> groups states of a configuration with the same $L$ and $S$. An <atomic fine-structure level> additionally specifies $J$; <spin-orbit coupling> can split one term into several such levels. In zero external field, a level retains $2J+1$ magnetic substates.
The <term symbol> is
$$
\boxed{{}^{2S+1}L_J,}
$$
with letters $S,P,D,F,G,\ldots$ denoting $L=0,1,2,3,4,\ldots$. The superscript is the <spin multiplicity>. Without the $J$ subscript, ${}^{2S+1}L$ identifies an <atomic term>, rather than an individual fine-structure level.
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