From The Collaborative International Dictionary of English v.0.48 [gcide]:
Euchologion \Eu'cho*lo"gi*on\, Euchology \Eu*chol"o*gy\, noun [NL. euchologion, Gr. ? prayer book; ? prayer, vow (fr. ? to pray) + ? to say, speak.] (Eccl.) A formulary of prayers; the book of offices in the Greek Church, containing the liturgy, sacraments, and forms of prayers.
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