mouthful Get Printable Handwriting (mouth-ful) 2 syllables Rhymes Learn It! Spelling Test Definition noun. 1 the quantity that can be held in the mouth; 2 a small amount eaten or drunk; 3 a long word or phrase that is difficult to say Example Sentence She ate her soup one mouthful at a time. Synonyms bite; gulp; taste Antonyms plateful Rhymes Two Syllable Rhymes (1) mouthful Share with your friends: