I've always been meaning to start a list of these.
効果的 effective, successful
具体的 concrete, tangible, definite
一般的 popular, typical, general
基本的 fundamental, standard, basic
All な, by the way.
These pop up all over. The "teki" is...I guess sort of like "ish" in that it's an ending that makes things an adjective. I guess this is all I can come up with off the top of my head, but maybe we'll make this an ongoing series. They seriously spring up all over.