Merriam-Webster's Collegiate® Dictionary, 11th Edition
MUCK
I. noun
Etymology: Middle English muk, perhaps from Old English -moc; akin to Old Norse myki dung
Date: 13th century
soft moist farmyard manure, slimy dirt or filth,
3. defamatory remarks or writings, rubbish , nonsense ,
4. a. dark highly organic soil, mire , mud , something resembling muck ; gunk , material removed in the process of excavating or mining, mucky adjective
II. verb
Date: 14th century
transitive verb
1. to clean up, to clear of muck, to dress (as soil) with muck, to dirty with or as if with muck ; soil , intransitive verb to move or load muck (as in a mine),
2. to engage in aimless activity, putter , tinker , interfere , meddle , mucker noun