The Collaborative International Dictionary
Lectionary \Lec"tion*a*ry\, n.; pl. -ries. [LL. lectionarium, lectionarius : cf. F. lectionnaire.] (Eccl.) A book, or a list, of lections, for reading in divine service.
Wiktionary
n. A book or listing that contains a collection of readings for Christian worship.
Wikipedia
A lectionary is a book or listing that contains a collection of scripture readings appointed for Christian or Judaic worship on a given day or occasion. There are sub-types such as a "gospel lectionary" or evangeliary, and an epistolary with the readings from the New Testament Epistles.
Usage examples of "lectionary".
He thumbed with appreciation the Lectionary and took down the censer and incense boat and spoon and counted the candles and candlesticks.
Look in the lectionary, if you like, but it will not tell you more than that.
The Lectionary was open to the Second Epistle of Paul to the Corinthians.
He now began an attack on the proposal for a new lectionary for the Church of England, based largely upon his objections to the principles for determining the authority of MS.
Then there are also lectionaries, which contain New Testament Scripture in the sequence it was to be read in the early churches at appropriate times during the year.
The few small windows were open as well, shutters tied back against the wall, but even so at the central lecterns it was dim work for the monks copying missals and lectionaries.