Oxford Dictionary English mix up phrasal verbphrasal verb Add to my wordlistjump to other resultsPhrasal Verbs mix somethingup Add to my wordlistjump to other results to change the order or arrangement of a group of things, especially by mistake or in a way that you do not want synonym muddle Someone has mixed up all the application forms. related noun mix-up mix somebody/something up (with somebody/something) Add to my wordlistjump to other results to think wrongly that somebody/something is somebody/something else synonym confuse I think you must be mixing me up with someone else. see also mixed up oxfordlearnersdictionaries.com