The Collaborative International Dictionary of English v.0.48:

Pneumatothorax \Pneu`ma*to*tho"rax\, n. [Pneumato- + thorax.]
   (Med.)
   See Pneumothorax.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Pneumothorax \Pneu`mo*tho"rax\, n. [Gr. ? air + E. thorax.]
   (Med.)
   A condition in which air or other gas is present in the
   cavity of the chest; -- called also pneumatothorax.
   [1913 Webster]