intermarry with (someone)
1. To wed someone who is part of a different group (i.e. race, religion, clan, etc.). I was raised Catholic, but I'm going to intermarry with a Jew because she happens to be the love of my life.
2. To wed someone who is part of one's same group (i.e. race, religion, clan, etc.). As a devout Catholic, it was important for me to intermarry with a Catholic.
intermarry with someone
[for members of a group] to marry into another group, race, or clan. Our people don't intermarry with people of that clan. They do not intermarry with other groups on purpose.