What is the side seam?

Question

For example they tell you the length of the side seam of a dress is 26 inches, so where do you start measuring from?

Answer 1

If it's a dress, start measuring the seam from under the arm pit down to the bottom of the hem.

Answer 2

On pants it at the waist line down.-look carfully- these are not the same at all.
Side seam- waist to floor
In seam- from crotch to floor

Wear the "shoes" you intend to wear often with that pant, when having it measured for alterations.