In this group of languages charge is incomplete (5)
I believe the answer is:
indic
'in this group of languages' is the definition.
Although both the answer and definition are singular nouns, I don't understand how they can define each other.
'charge is incomplete' is the wordplay.
'charge' becomes 'indict' (indicting is a kind of charging).
'is incomplete' means to remove the last letter.
'indict' with its last letter removed is 'INDIC'.
Can you help me to learn more?
(Other definitions for indic that I've seen before include "Group of languages including Sanskrit" , "Language" , "Like some tongues" .)