A heist is a robbery or theft , especially one involving a large amount of money or valuable items. It is often carefully planned and executed by a group of criminals. HEIST definition: 1. a crime in which valuable things are taken illegally and often violently from a place or person…. Learn more. Definition of heist noun from the Oxford Advanced Learner's Dictionary. an act of stealing something valuable from a shop or bank synonym robbery. It’s a tense thriller about a diamond heist that goes badly wrong. Questions about grammar and vocabulary? The meaning of HEIST is hoist. How to use heist in a sentence.