Definition of "spirilla" []

• Any flagellated aerobic bacteria having a spirally twisted rodlike form (noun)

WordNet. Princeton University. 2010.

• "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."
• "But a resting state of the comma bacilli has never been met with -- a very exceptional thing in the case of bacilli, and another reason why the organism must be regarded rather as a spirillum than a bacillus, for the spirilla require only a fluid medium, and do not, like the anthrax bacilli, thrive in a dry state."
• "As early as 1873, spirilla were demonstrated in relapsing fever."