A person who believes in or practices execution; in music, a technical performer focused on execution (skill in playing).
From execution plus -ist (suffix for one who practices or believes in something). The musical sense developed in the 19th century.
In 19th-century music criticism, 'executionist' was sometimes used dismissively—critics would say a performer was merely an 'executionist' lacking interpretation or artistry, showing how the same word could be both compliment and insult depending on context.
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