Cough  —v. 1 expel air etc. From the lungs with a sudden sharp sound. 2 (of an engine etc.) Make a similar sound. 3 slang confess. —n. 1 act of coughing. 2 condition of respiratory organs causing coughing.  cough up 1 eject with coughs. 2 slang bring out or give (money or information) reluctantly. [imitative, related to dutch kuchen]