A match in Zoroastrian writings collection (6)
I believe the answer is:
avesta
'zoroastrian writings collection' is the definition.
(sacred texts of Zoroastrianism)
'a match' is the wordplay.
'match' becomes 'vesta' (type of historical wooden match).
'a'+'vesta'='AVESTA'
'in' acts as a link.
(Other definitions for avesta that I've seen before include "sacred text" , "collection of sacred writings" , "Parsee scriptures" , "collection of holy writings" , "Zoroastrian scriptures" .)