Ceramic sintered body and plasma-generating electrode

A ceramic sintered body, which comprises

• a first particular element consisting of five or six elements selected from among the group consisting of titanium (Ti), vanadium (V), zirconium (Zr), niobium (Nb), molybdenum (Mo), hafnium (Hf), tantalum (Ta), and tungsten (W);
• a second particular element consisting of one element selected from the group consisting of yttrium (Y) and aluminum (Al);
• and
• elemental carbon (C), wherein
• a total amount of the first particular element, the second particular element, and elemental carbon is 98 at % or more;
• the ceramic sintered body has a plurality of microstructures having respective compositions different from one another;
• one of the plurality of microstructures includes a solid solution containing at least three members of the first particular element.