[bloo-tuhng] 
| a viral disease of sheep and sometimes cattle, transmitted by biting insects and characterized by high fever, excessive salivation, swelling of the face and tongue, and cyanosis of the tongue. |
| blue·tongue (blōō'tŭng') n. A viral disease of sheep and cattle that is transmitted by biting insects and is characterized by fever, the formation of oral lesions, and swelling and cyanosis of the lips and tongue. |
