at least say hello인사 means “greeting” or “hello,” and 라도 adds the meaning “at least” or “even.” Used when suggesting that someone greet others before leaving or as a minimum courtesy.
KO: 잠깐 들렀으니 선생님께 인사라도 하고 가자.
EN: Since we stopped by, let’s at least say hello to the teacher before we go.