MSiS

English edit

MSiS (plural MSiSs)

(anthropology) Initialism of mother's siblings's son.; male maternal cousin
- 1941, Paul K. Benedict, Kinship in Southeastern Asia:
  The Dafla sibling and cousin terminology differs considerably from that found in Abor - Miri . ... distinct terms are used for the corresponding maternal cousins ( MSiD, MsiS ), and age distinctions are not made in the xC terms.