muck (sth) out meaning, definition, what is muck (sth) out: to clean a place where a large animal lives, especially a stable, by removing the waste. Learn more. 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. muck (sth) out Bedeutung, Definition muck (sth) out: to clean a place where a large animal lives, especially a stable, by removing the waste. Your fucking cat has just had a muck out all over the fucking floor. These words appear in red, and are graded with stars. She'd spent all morning mucking out the horses. Say brolast night I gave Sharlene a good mucking. The action of cleaning a stable. Dictionary apps Browse our dictionary apps today and ensure you are never again lost for words.