The most common and most likely answer to this crossword clue is the 10 letter word MORGANATIC
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More clues leading to the result MORGANATIC
Buddy explains!
The straight part
We know that "unequal when referring to marriage" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case unequal when referring to marriage = morganatic.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does MORGANATIC mean?
MORGANATIC adjective- Designating a marriage (or the wife involved) between a man of higher rank and a woman of lower rank, often having various legal repercussions (typically that such a wife has no claim on the husband's possessions or title). It was not an aspect of English law, but was common in other royal houses, especially in Germany.