Does shell over shell mean the same as shell in shell in crochet?

shell over shell means make a shell in the middle stitch of the shell below .. if your shell is a 5 stitch shell then make a shell in the 3rd stitch of the shell below .......... if it is a 7 stitch shell make the shell in the 4th stitch of the shell below .... etc .. you are making a shell over the existing shell in the middle stitch ..