Where does “అంకమ్మ” come from?

అంకమ్మ (Telugu) comes from Telugu అమ్మ, from Proto-Dravidian amma — mother.

Ancestry of “అంకమ్మ”, step by step

Step	Language	Word	Meaning
1	Telugu	అమ్మ	mother
2	Proto-Dravidian	amma	mother