adelphogamy
noun
ad·el·phog·a·my
ˌa-dᵊl-ˈfä-gə-mē
plural -es
1
: polyandry in which brothers have a wife or wives in common
2
zoology : mating of brothers and sisters (as in some ants)
3
: union of mother and daughter cells (as in some yeasts)
Word History
Etymology
adelpho- + -gamy
First Known Use
1888, in the meaning defined at sense 1