Designer jeans are jeans that were made from the late 1970s to the mid 1980s (usually for women, but some for men too) that were skintight, and had designs on them in the butt area. Popular brands were
Jordache[?],
Sergio Valente[?],
Sasson[?],
Gloria Vanderbilt,
Chic,
Calvin Klein[?],
Bonjour[?] and others.