From Longman Dictionary of Contemporary Englishknock somebody/something back phrasal verb informal1 knock something ↔ backDRUNK to quickly drink large quantities of a drink, especially an alcoholic drink Brenda knocked the brandy back quickly.2 knock somebody back somethingCOST to cost you a lot of money His new car knocked him back several thousand dollars.3 knock somebody back British EnglishSURPRISEDSHOCK to make someone feel upset, shocked, or physically weak → knock→ See Verb table
