"Side crunches" refers to a specific exercise where you lie on your side and crunch your torso towards your hip, targeting and strengthening the muscles on the sides of your abdomen. Full definition
Start hitting the right muscles, in the right ways, the right number of times with the standing side crunch with high kick. (womenshealthandfitness.com.au)
Side crunch with hip lift: Start with one arm reaching straight up. (health.com)