They share a sense of regret and sadness but still have distinct meanings. *안타깝다: You are sad and feel bad because you *can't do much about something*. "그가 어렵게 사는 것이 안타까웠다". *아깝다: You feel bad because something is *wasted*. "그는 재능이 많은데 아깝게도 살리지를 못하고 있다." "아까운 사람이다." (Too bad he is not fulfilling his potential) *아쉽다: You feel sad because you can't have more of something (taken away too soon). "아쉽게 헤어져야 했다." (You wanted to stay together longer but had to part)

They are similar, but not the same. 안타깝다: It's mostly used when you feel sorry/sad about something bad happening to someone else. - 병원 옆자리 환자의 수술이 잘못되어 안타깝다 ============================================================== 아깝다: It's when you feel bad about missing a good chance or paying unnecessary expenses. - 방금 빗나간 슛은 정말 아깝다. - 어제 택시기사한테 바가지 쓴 돈이 아깝다. 아쉽다: It's when you are inconvenienced with the outcome, or feeling the lack of something/someone. - 어제 경기 결과는 아쉽다 - 이 요리에는 야채가 부족한 것이 아쉽다.