The name of a pant cut really only tells you one thing: how close the fabric sits to your leg.
Skinny sits closest, from the thigh all the way down. Slim holds the thigh but eases off a little below it. Straight falls in one width from knee to ankle. Regular is roomier than all three, without ever reading as oversized.
Here is what makes it confusing: every brand interprets these names its own way. One label's slim can be as loose as another label's straight. So the word in the product title is a rough signal, not a measurement.
How to choose without trying them on
Take the best-fitting pair of pants in your wardrobe right now. Lay them flat on the floor and measure three things: the waist, the hip, and the thigh width. Match those numbers against the size table on the product page.
If your numbers land between two sizes, take the larger one. A waist that runs slightly loose can still be handled with a belt or a tailor. A thigh that runs too tight can't be fixed at all.
If you're still unsure
Slim, in an ankle length. Neat enough for the office, not so tight that it wears on you across a full day, and a cut that doesn't start looking dated quickly.
What I avoid for a first purchase online: skinny. Not because the cut is unflattering, but because the outcome comes down almost entirely to your thigh measurement — and that is the one number hardly any brand publishes.
