Intermarriage means the bride and groom are from different demographic groups, such as religion or ethnic background. Historically, intermarriage was considered unacceptable in many places, but it is increasingly accepted today.
One common intermarriage situation is a marriage between two people of different religions or faiths, a practice that is condemned for Christians in the Bible. The Bible does not forbid interracial marriage or marrying outside of one's own culture. In the United States at present Buddists and the religiously unaffiliated are the most likely to marry outside their own faith, while Mormons and Hindus are the least likely.
References
1. For mainline Protestants, evangelical Protestants and historically black Protestants, this category includes marriages and partnerships between people from different Protestant denominational families (e.g., a Methodist married to a Lutheran).
Source: Pew Forum U.S. Religious Landscape Survey, [1] conducted in 2007 and released in 2008. Based on respondents who say they are married and respondents who say they are living with a partner. Results for other religious groups are not reported due to small sample sizes. Due to rounding, figures may not add to 100.