A "pinky promise" is a promise that is not allowed to be broken. You make the promise with the other person by entwining your pinky fingers together. It's like a cute kind of handshake. Keep in mind this is done between children, and is not considered standard business practice.

hmm, are you talking about the pinky finger? Pinky's the smallest finger. Hope this link helps. http://en.wikipedia.org/wiki/Little_finger

The little finger, often called the pinky in American English.

What does "pinky" mean? What's the meaning of (the word) "pinky"?

adjectıve of the colour pink.. dıctıonary.com