Two Thumbs Up Meaning

(dated) A hand gesture indicating strong approval.

Example: 1935 Jul 7, “GLOSSARY OF RADIO'S NEW TERMS COMPILED”, Los Angeles Times:
  Two thumbs up means everything om time and perfect.
1963 Oct 18, “Three More Negroes Register To Vote In Louisiana Town”, Toledo Blade:
  As he walked out of the court house, he showed two thumbs up and reached in his pocket to display his registration slip to some 30 other Negroes