marry out

verb2

1. •
   To marry someone who is from another family; To avoid incest.

   • Most of us take it for granted that we must marry out—that is, we cannot marry members of our immediate families. — 1994
2. •
   To marry someone from a different religion or ethnic group.

   • The opposite supposition is that younger people are more receptive to social change and unconventional ways, thus more likely to marry out at a higher rate. — 1990