empyema
Concise Oxford English Dictionary © 2008 Oxford University Press:
empyema /ˌɛmpʌɪˈiːmə/
▶noun Medicine the collection of pus in a body cavity, especially in the pleural cavity.
– origin ME: via late L. from Gk empuēma, from empuein ‘suppurate’.
'empyema' also found in these Oxford entries:

