The state, quality, or condition of being bridal or bride-related; archaic term for bride-like characteristics or bridal status.
From bridale or bridal plus abstract noun suffix -ty/-ity. This rare word formation attempts to create an abstract noun from bridal adjectives, very uncommon in modern English.
Bridalty is the kind of ultra-rare medieval word-construction that shows how experimentally English speakers played with suffixes—they'd try -ty on almost anything to see if it would stick.
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