Overall and blue jeans, called dungarees, were a necessary clothing item for laborious tasks. WWII made blue jeans more popular as working Rosies took to factories and Land Girls worked farms.
Men’s blue jeans had a loose fit, long crotch, and a wide rolled cuff. Women’s cut jeans had a narrowed leg (that was still rather boxy), curved hip, and a side zipper. Some women’s versions had buttons like men’s sailor pants.
In 1948, Wrangler invented the front zip up jeans for women. Women didn’t like the new front zip, at least not until the 1950s.