Chant from choir, originally in Latin, modified in church (8)
I believe the answer is:
canticle
'chant' is the definition.
(thesaurus)
'choir originally in latin modified in church' is the wordplay.
'originally' suggests taking the first letters.
'in' indicates putting letters inside.
'modified' indicates anagramming the letters.
'in' indicates putting letters inside.
'church' becomes 'ce' (abbreviation for Church of England).
The first letter of 'choir' is 'c'.
'latin' anagrammed gives 'antil'.
'c' going inside 'antil' is 'anticl'.
'anticl' inserted into 'ce' is 'CANTICLE'.
'from' is the link.
(Other definitions for canticle that I've seen before include "Church hymn or chant" , "Short hymn" , "Liturgical song" , "eg Magnificat" , "is heard in church" .)