Definition of premaritally in English:

premaritally

adverb

See premarital

‘A 2004 study by psychologist Scott Stanley, based on a national phone survey of nearly 1,000 people, found that men who had lived with their spouse premaritally were on average less committed to their marriages than those who hadn't.’
‘In the early 1960s, 60 percent of all premaritally pregnant women under 30 married before the birth of their child.’