Taneiev, Sergei Ivanovich (syĭrgāˈ ēväˈnəvĭch tənyāˈəf) [key], 1856–1915, Russian composer and teacher. He studied at the Moscow Conservatory under Nicholas Rubinstein and Tchaikovsky, succeeding the latter as professor of harmony and orchestration in 1878; he served as director of the conservatory from 1885 to 1889 and taught composition there from 1889 to 1906. Taneiev composed an opera on Aeschylus' Orestes (1895), cantatas, symphonies, chamber music, and songs. A highly intellectual musician, he wrote several theoretical treatises. In his teaching, he guided a whole generation of composers including Scriabin, Rachmaninov, and Glière.