Able to change Latin tag (5)
I believe the answer is:
label
'tag' is the definition.
(I know that tag can be written as label)
'able to change latin' is the wordplay.
'to change' is an anagram indicator.
'latin' becomes 'l' ().
'able' is an anagram of 'labe'.
'labe'+'l'='LABEL'
(Other definitions for label that I've seen before include "Name-tag" , "attachment to the Christmas parcel" , "Classifying name" , "Mark" , "Identity tag" .)