From Longman Dictionary of Contemporary Englishshake somebody/something ↔ up phrasal verb1 SHOCKto give someone a very unpleasant shock, so that they feel very upset and frightened She was badly shaken up by the accident. → shaken2 CHANGE/MAKE something DIFFERENTto make changes to an organization in order to make it more effective SYN overhaul the government’s plans to shake up the educational system → shakeup → shake→ See Verb table
Examples from the Corpus
shake up• Dole is no fresh breeze blowing in from the hinterland to shake things up.• In the second half Hereford shook themselves up.• The storm shakes me, like the scare that shook me up a year ago, tearing me from the commonplace.• The town needs a feisty, right-wing tabloid to shake it up, to have a debate.• But he seemed to want to shake things up, to outrage me.• Not so much the opposition - what shook me up was to see children being used in the front line by protestors.• Carlton then took a small scoopful of concrete and shook it up with alcohol to see how much air was dissolved.From Longman Business Dictionaryshake something ↔ up phrasal verb [transitive] to make changes in an organization or system to make it more successful, effective etcThey restructured organizations and introduced competition, to shake up monopolies perceived as inefficient and complacent. → shake→ See Verb table 