Morganatic
/ˌmɔːrɡəˈnætɪk/
Definition 1 of 1
Pro Tip 1/3Historical Context
Morganatic was more common in royal or noble contexts, particularly in Europe, to describe unequal societal-status marriages. 
Prince Alexander's morganatic marriage barred his children from succession.
Pro Tip 2/3Limited Rights
The lower-ranking spouse in a morganatic marriage does not gain the rights usually associated with marrying into a higher rank. 
Despite being married to a duke, her morganatic status meant she had no claim to his estates.
Pro Tip 3/3Inequality Emphasis
'Morganatic' underlines the inequality between spouses regarding social status or title inheritance. 
Their morganatic union was seen as controversial due to the disparity in their social standings.