outbreak Get Printable Handwriting (out-break) 2 syllables Rhymes Learn It! Spelling Test Definition noun. 1 a sudden breaking out 2 a sudden breaking out or increase in activity of disease. Example Sentence The doctor was concerned about an outbreak of measles. Synonyms burst; eruption; outburst Antonyms contained; confined Rhymes Two Syllable Rhymes (1) outbreak Share with your friends: