Jeans
Cut names like "straight," "slim," or "relaxed" aren't standardized across brands, so the same name can describe genuinely different amounts of room through the thigh and leg opening depending on who makes the jeans. A "slim straight" at one brand can measure closer to another brand's "relaxed" cut at the identical waist size — the cut name is a starting point, not a guarantee of a specific silhouette.
Rise still does most of the work in how a pair of jeans actually sits, independent of the leg cut: a high-rise straight jean and a low-rise straight jean in the same waist size will sit at noticeably different points relative to the natural waist, which changes how the whole leg reads even when the thigh and hem measurements are identical.
Denim weight and stretch percentage decide how a pair wears in over time. A rigid, low-stretch denim holds its cut measurements and typically needs to fit snug when new, since it will relax slightly with wear; a denim with a higher stretch percentage fits closer to true-to-size from the first wear and holds that fit rather than continuing to loosen.
Jeans at retailers

Gap
Straight Jeans

Gap
Straight Jeans

Old Navy
Straight Jeans

Gap
Straight Jeans

Old Navy
Straight Jeans

Uniqlo
Straight Jeans

Uniqlo
Straight Jeans

Uniqlo
Straight Jeans

Uniqlo
Straight Jeans

Uniqlo
Straight Jeans

Uniqlo
Straight Jeans

Uniqlo
Straight Jeans
Calvin Klein
Calvin Klein Men's 90s Straight Jeans - Black - 29W x 30L
Calvin Klein
Calvin Klein Men's Slim Straight Jeans - Grey - 36W x 30L
Calvin Klein
Calvin Klein Men's Slim Straight Jeans - White - 36W x 32L
Calvin Klein
Calvin Klein Men's Slim Straight Jeans - Blue - 29W x 30L
Calvin Klein
Calvin Klein Women's 90s Straight Jeans - Blue - 30W x 33L
Calvin Klein
Calvin Klein Women's High Rise Straight Jeans - Blue - 30W x 33L
Calvin Klein
Calvin Klein Women's High Rise Straight Jeans - Black - 27W x 29L
Calvin Klein
Calvin Klein Men's 90s Straight Jeans - Blue - 32W x 30L