any of a class (Mollicutes) of bacteria that lack cell walls and may cause disease, esp. of the joints and lungs, in humans and domestic animals, or may be pathogenic for plants
Origin:
ModL: see myco- & plasma
See mycoplasma in American Heritage Dictionary 4
noun
Any of numerous parasitic, pathogenic microorganisms of the genus Mycoplasma that lack a true cell wall, are gram-negative, and need sterols such as cholesterol for growth. In humans, one species is a primary cause of nonbacterial pneumonia. Also called pleuropneumonia-like organism.