Definition of spirillum in US English:



  • A bacterium with a rigid spiral structure, found in stagnant water and sometimes causing disease.

    Genus Spirillum; Gram-negative

    • ‘Possibly it is a true spirillum, portions of which appear in the comma shape, much as in other spirilla - e.g., spirilla undula, which do not always form complete spirals, but consist only of more or less curved rods.’
    • ‘These very long, spiraled nascent bdellovibrio were proposed earlier from electron microscope images to be common in spirilla, which are long and coiled themselves.’
    • ‘The retention of the normal shape that we observed may be caused by steric restrictions on a major change in shape and size by neighboring spirilla and bdellovibrios.’


Modern Latin, irregular diminutive of Latin spira ‘a coil’.