Learn the meaning of hook up as a phrasal verb, a noun, and a slang term for sex or connection. Find out how to use hook up in different contexts and languages with Cambridge Dictionary. Learn how to use the idiom " hook up " in different contexts and meanings, from casual sexual encounters to connecting devices. Explore its synonyms, antonyms, cultural variations, and practical exercises. Learn the difference between hook up as a phrasal verb and hook up with a person. Hook up can mean to connect objects, meet someone, or have a casual sexual encounter, depending on the context. Definition of hook up phrasal verb in Oxford Advanced American Dictionary. Meaning , pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.