plainchant

(also `plainsong / -sCN; -9sRN/) n [U] medieval type of church music for a number of voices singing together, used in the Anglican and Roman Catholic Churches 素歌（中世纪的宗教合唱曲, 为圣公会及天主教所采用）.

placenta, placental, placid, placidity, placidly, placket, plagiarism, plagiarist, plagiarize, plagiarize, plagiarise, plague, plague-ridden (also `plague-stricken), plaice, plaid, plain, plain clothes (esp of police officers), plain dealing, plain flour, plain-clothes man, plain-spoken, plainly, plainness, plains, plainsman, plaint, plaintiff, plaintive, plaintively, plaintiveness, plait, plan, plane, plane geometry, plane sailing, plane-table, planet, planetarium, planetary, plangency, plangent,