acorn Get Printable Handwriting (a-corn) 2 syllables Rhymes Learn It! Spelling Test Definition noun. the roundish oneseeded thinshelled nut of an oak tree usually having a woody cap Example Sentence The squirrel buried the acorn. Synonyms oak nut; nut; fruit of the oak tree Antonyms oak tree Rhymes Two Syllable Rhymes (1) acorn Share with your friends: