bit-player laments the confusing system of names used to identify complexity classes.
The letter P generally stands for “polynomial” (except where it’s “probabilistic”). N usually denotes “nondeterministic” (but NC is “Nick’s Class”). Likewise the prefix D is for “deterministic” (except that it’s usually omitted, and sometimes it means “difference” or “dynamical” instead). B stands for “bounded-error” (except that BH is “Boolean hierarchy” and “BPd(P)” is “Polynomial Size d-Times-Only Branching Program”). Q is for “quantum” (except “QH” is the “query hierarchy” and “QP” is “quasi-polynomial time”).
The sad truth is, the naming conventions for furniture at Ikea make for a more consistent language than those of complexity theory.
Hmm. Maybe the math and CS guys should talk to the bioinformaticians that gave us Pokemon as the name of an oncogene, until (under threat of legal action) it was renamed Zbtb7.