If someone or something shakes something to the foundations or shakes it to its foundations, they damage it, change it or shock it very much. Her faith, which had been so strong, was shaken to the foundations. When an American president is forced to resign, the country is shaken to its foundations. Note: The verb rock is sometimes used instead of shake. The music industry was rocked to its foundations last night when it was revealed that the Midlands' top live music venue was to close.