also thumbs up
1.
A ~ or a ~ sign is a sign that you make by raising your thumb to show that you agree with someone, that you are happy with an idea or situation, or that everything is all right.
She checked the hall, then gave the others a ~ sign.
N-SING
2.
If you give a plan, idea, or suggestion the ~, you indicate that you approve of it and are willing to accept it. (INFORMAL)
The financial markets have given the thumbs up to the new policy...
? thumbs-down
N-SING: the N