n. An acute infectious disease caused by the bacterium Corynebacterium diphtheriae, which infects mucous membranes of the throat, causing formation of a thick layer called the false membrane that can obstruct breathing, and producing a potent toxin that enters the bloodstream and causes systemic effects that include damage to the heart and nervous system. [New Latin diphthēria, from French diphthérie, from Greek diphtherā, piece of hide, leather; see LETTER.] diph′the·ritic (-thə-rĭtĭk), diph·theric (-thĕrĭk), diph·theri·al adj. |
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