| an extraordinary or unusual thing, person, or event; an exceptional example or instance. |
| a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison. |
| effervescence (ěf'ər-věs'əns) Pronunciation Key
The bubbling of a solution due to the escape of gas. The gas may form by a chemical reaction, as in a fermenting liquid, or by coming out of solution after having been under pressure, as in a carbonated drink. |