How many letters does the top answer for “of or relating to a marriage partner” have?

The most common answer is mated (5 letters).

Crossword clue: of or relating to a marriage partner

1 answer found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

mated 5 letters wn-def

of or relating to a marriage partner

a person's partner in marriage 50% similar → spouse

of or relating to a wedding or marriage 50% similar → hymeneal

of or relating to the state of marriage 50% similar → marital, matrimonial