• WordNet 3.6
    • adj invitatory conveying an invitation "a brief invitatory note"
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Webster's Revised Unabridged Dictionary
    • n Invitatory That which invites; specifically, the invitatory psalm, or a part of it used in worship.
    • a Invitatory Using or containing invitations. "The “Venite” [Psalm xcv.], which is also called the invitatory psalm."
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Century Dictionary and Cyclopedia
    • invitatory Using or containing invitation.
    • n invitatory A form of invitation used in religious worship; something consisting of or containing invitation in church service.
    • n invitatory Specifically— A form of exhortation to praise; especially, in the daily office of the Western Church, the variable antiphon to the Venite at matins. In the Anglican matins or morning prayer the versicle “Praise ye the Lord” (founded on the former “Alleluia” or “Laus tibi”), with its response, “The Lord's name be praised,” serves as unvarying invitatory. In the Greek Church the invariable invitatory is the triple “O come, let us worship … (Δευ%21τε, προσκυνήσ, σ1ωμεν …)” before the psalms at each of the canonical hours.
    • n invitatory An early name of the Roman introit.
    • n invitatory Any text of Scripture chosen for the day, and used before the Venite or 95th Psalm.
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Chambers's Twentieth Century Dictionary
    • adj Invitatory using or containing invitation
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Webster's Revised Unabridged Dictionary
LL. invitatorium,: cf. F. invitatoire,
Chambers's Twentieth Century Dictionary
Fr.,—L. invitāre, -ātum.


In literature:

I will write an invitatory song to the EDITOR.
"The Knickerbocker, or New-York Monthly Magazine, April 1844" by Various
An example of this early and more elaborate use survived in the Breviary in the treatment of the Venite as an Invitatory Psalm.
"The Christian Use of the Psalter" by A. R. Whitham