The lexical variants presented in the note below are arranged according to their frequency of occurrence in the survey data-from most frequent to least frequent.

The word sasu is observed for both the concepts ‘egos husband’s mother’ and ‘ego’s wife’s mother’ in all districts of Maharashtra. The following variation was noted for the two concepts in different dialects of Marathi:

sasu, sasubai, atya, atyabai, atti, sas, sasus, mami, hau ,hao, pʰui, hawḍi etc.

The customs regarding who can marry whom in a consanguineous marriage vary across southern, central, and northern regions of India. In many of the southern regions, it is a customary practice to get one's father's sister's son/daughter married to the mother’s brothers daughter/son. In such cases, the words used to refer to ‘ego’s husband’s mother’ and ‘ego’s wife’s mother’ provide an insight into different customs of the Indian marriage system.

In Karve’s (1953: 165) view, the word sasu has originated from Sanskrit. The SDML survey shows that the word mami, which is typically used to refer to ‘ego's mother's brother’s wife’, is also used to refer to ‘ego’s husband’s mother/ ego’s wifes mother’. Similarly, the word atya which is used to refer to ‘ego’s father’s sister was noted as an alternative word for sasu in some parts of Maharashtra. The word pʰui was reported in Chinchavali village of Raigad district and Manejavalga village of Latur district; it was also observed in the tribal regions of Nashik district.

References:

Karve, Iravati. 1953. Kinship Organisation in India. Pune: Deccan College Monograph series 11.