someone who teaches a choir to sing together 唱诗班[合唱团]指挥
Examples from the Corpus
choirmaster• Her choirmaster said her voice, now a low alto, was just too low.• Mozart had become acquainted with the choirmaster there, Anton Stoll, for whom he wrote the exquisite motet Ave verum corpus.• The choirmaster was then arrested but has not yet been charged.