I.up [美 əp, 英 ʌp]副up often appears as the second element of certain verb structures in English (back up, pick up, sit up, etc). For translations, see the relevant verb entry (back, pick, sit, etc).
Now, neuroscience researchers have created an algorithm to reveal key insight into why the brain can sometimes muddle up one of the most fundamental aspects of the human experience.
Unlike an awkward run-in at a social mixer if you muddle up your relationship building with a new neighbour they don't go away at the end of the night.
The countless number of products that promise shine, strength, and color can also muddle up our idea on what we need to do and use for our crowning glory.