What is it that you should keep after giving it to someone else?

Why this works

This riddle plays on the concept of a "word" having two meanings: it can refer to a spoken promise or commitment and the literal word itself. When you give someone your word, you are promising to do something or to keep a commitment, yet you still retain the integrity of that promise. Thus, you keep your word in the sense of maintaining your promise, even after you have given it to someone else. It’s a clever twist on the idea of sharing something while still holding onto its significance!