What is another word for "azygous"?

Roget's Thesaurus (1911) lists these synonyms for "azygous": abstract, ace, alone, and, apart, atomic, axial, axis, backbone, beat, bring, buoyancy, but, center, central, centrality, centralization, centralize, centrally, centrical, column, combine, compact, concentrate, concentration, concentric, converge, convergence, core, desolate, dine, disjoin, disjunction, dreary, else, eye, first, focal, focus, fort.