Grade 1 muck Get Printable Handwriting (muck) 1 syllables Learn It! Spelling Test Definition noun. andverb. organic matter in decomposition; manure; wet soil or mud with a high organic content; dirt or filth esp. if it is moist and sticky Example Sentence The pig's snout was covered with muck. Synonyms soil; dirt; filth; manure Antonyms cleanliness; pureness; sterility Share with your friends: