diph•the•roidPronunciation: (dif'thu-roid", dip'-), [key]
resembling diphtheria, esp. in the formation of a false membrane in the throat.
any bacterium, esp. of the genus Corynebacterium,
that resembles the diphtheria bacillus but does not produce diphtheria toxin.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.