The Collaborative International Dictionary of English v.0.48:

Chin cough \Chin" cough"\ [For chink cough; cf. As. cincung long
   laughter, Scot. kink a violent fit of coughing, akin to MHG.
   k[imac]chen to pant. Cf. Kinknaust, Cough.]
   Whooping cough.
   [1913 Webster]