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Webster 1913 Edition
Improperia
‖
Imˊpro-pe′ri-a
,Noun.
 pl.
 [L., reproaches.] 
(Mus.) 
A series of antiphons and responses, expressing the sorrowful remonstrance of our Lord with his people; – sung on the morning of the Good Friday in place of the usual daily Mass of the Roman ritual. 
Grove.
 Definition 2025
Improperia
Improperia
See also: improperia
English
Noun
Improperia pl (plural only)
- A series of antiphons and responses expressing the remonstrance of Jesus Christ with his people, usually sung on Good Friday.
 
improperia
improperia
See also: Improperia
Latin
Noun
improperia
- nominative plural of improperium
 - accusative plural of improperium
 - vocative plural of improperium