Define muck out. muck out synonyms, muck out pronunciation, muck out translation, English dictionary definition of muck out. noun dung, filth, rubbish etc. farm. Define muck (verb) and get synonyms. What is muck (verb)? muck (verb) meaning, pronunciation and more by It was always my job to muck out the barn. One side has the word, one side has the definition. by prolonged floods, especially when referring to a large area being cleaned; mucking out buildings. The action of cleaning a stable. Word by Word Definitions muck play. Navigation telefonnummern von stars Personal tools Not logged in Talk Contributions Create account Log in. Learn a new word every day. Trending Words Most popular in the world Australia Canada India Malaysia Pakistan Spain the UK the US the world. From the M-W Editors.