Antiphon

Webster's Practical Dictionary- A Practical Dictionary of the Englih Language · 1884 · p. 30

anti-i'on, Antiphony, -tifo-nl, a. (Mits.) An anthem or psalm sung in alternate parts: a response. — Antiphtnal, Antiphon'ic, -phon'ical, a. — Antiph'onal, n. A book of antiphons or anthems.