plainsong

/ˈpleɪnˌsɔŋ/
noun
  1. A style of medieval church music sung by a single voice or a choir in unison, without harmony or instruments, often using a free rhythm.
    • She studied plainsong as part of her music history class.
    • Plainsong has a simple, haunting beauty that many people find calming.
    • The monks chanted plainsong during the evening service.
Synonyms
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