The phrase "main component" refers to the most important part or element of something. It is the key element that contributes the most to the overall structure or functionality of a system, object, or idea. Full definition
While the colors I have highlighted make for fantastic main components of a room, there will obviously be other hues that you'll want to pull in too. (mindbodygreen.com)
Made of chopped sweet potatoes with feta cheese between layers of eggplant, mint, pomegranate, and yogurt are also main components in the finished dish. (apronless.com)
Your story must be for an adult audience and have a thriller intrigue as main component. (publishersarchive.com)