diphtheria

Concise Oxford English Dictionary © 2008 Oxford University Press:
diphtheria /dɪpˈθɪərɪə, dɪf-/

▶noun a serious bacterial disease causing inflammation of the mucous membranes and formation of a false membrane in the throat which hinders breathing and swallowing.

– derivatives
diphtherial adjective,
diphtheritic /-θəˈrɪtɪk/ adjective,
diphtheroid adjective.

– origin C19: mod. L., from Fr. diphthérie, from Gk diphthera ‘skin, hide’.