Thumbs up or thumbs down is a hand gesture represented by a closed fist with your thumb pointing up or down in approval or disapproval respectively. (The cute hand in the Disneyland ad belongs to a fairytale world as it only has three fingers).
These gestures have become metaphors in English: "The audience gave the film the thumbs-up" means the audience liked the film.
The thumbs up gesture (and not the expression) is a serious insult in some cultures. It's fascinating how gestures vary worldwide, how emotions are the same in China, Iran or Italy but we use our hands and bodies to express them differently.
A gesture touching next to the eye might mean "I've seen a handsome man" or "I don't believe you", or "let's have a look" but if you don't know the language of gestures, you can't translate. :-)
Fist. The hand closed tightly with the fingers bent against the palm.Thumb. The first and shortest "finger" on your hand.